With 70,000 members posting items they would like to barter with or for, there is a good possibility you can find what you are looking for at U-Exchange. Listings are available from all over the world, and the search feature lets you narrow down your choices by keywords. There is no charge for membership or listings, as advertisers pay to sponsor the site.

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“Economic theory has always got to be historically bounded,” Beggs says. “I think it’s a mistake to think you’ll find the workings of modern money by going back to the origins of money.” He does point out that, while barter may not have been widespread, it’s possible that it happened somewhere and led to money, just given how much is unknown about such a large period of time.
An alternate currency, denominated in labour time, would prevent profit taking by middlemen; all goods exchanged would be priced only in terms of the amount of labour that went into them as expressed in the maxim 'Cost the limit of price'. It became the basis of exchanges in London, and in America, where the idea was implemented at the New Harmony communal settlement by Josiah Warren in 1826, and in his Cincinnati 'Time store' in 1827. Warren ideas were adopted by other Owenites and currency reformers, even though the labour exchanges were relatively short lived.[20]
Other anthropologists have questioned whether barter is typically between "total" strangers, a form of barter known as "silent trade". Silent trade, also called silent barter, dumb barter ("dumb" here used in its old meaning of "mute"), or depot trade, is a method by which traders who cannot speak each other's language can trade without talking. However, Benjamin Orlove has shown that while barter occurs through "silent trade" (between strangers), it also occurs in commercial markets as well. "Because barter is a difficult way of conducting trade, it will occur only where there are strong institutional constraints on the use of money or where the barter symbolically denotes a special social relationship and is used in well-defined conditions. To sum up, multipurpose money in markets is like lubrication for machines - necessary for the most efficient function, but not necessary for the existence of the market itself."[13]
In recent years, barter has enjoyed a resurgence as a means of countering economic insecurity, unemployment and worker exploitation. The nature of modern-day work, the pervasiveness of the Internet and the rise of social networking have all contributed to its spread. Other examples of alternative economic systems include gift economies, sharing economies and time banks.
Trade did occur in non-monetary societies, but not among fellow villagers. Instead, it was used almost exclusively with strangers, or even enemies, where it was often accompanied by complex rituals involving trade, dance, feasting, mock fighting, or sex—and sometimes all of them intertwined. Take the indigenous Gunwinggu people of Australia, as observed by the anthropologist Ronald Berndt in the 1940s:

And, if you’ve been in the Preparedness community for any amount of time, you are familiar with Fernando “Ferfal” Aguirre.  He wrote about his experiences of the economic collapse in Argentina in his very popular book,  The Modern Survival Manual: Surviving the Economic Collapse.  Argentina hasn’t really recovered from their collapse many years ago.  This video discusses one Barter Market Club that is located in an abandoned textile factory.

A place to exchange your books with other members, Bookins says that they have “more available books than the largest Barnes & Noble.” Best of all, there are no membership charges or fees to speak of. Bookins arranges all the trades for its users, so members never have to contact each other at all to set up swaps. Sending items is free of charge, while receiving an item costs $4.49.
Adam Smith, the father of modern economics, sought to demonstrate that markets (and economies) pre-existed the state, and hence should be free of government regulation[citation needed]. He argued (against conventional wisdom) that money was not the creation of governments. Markets emerged, in his view, out of the division of labour, by which individuals began to specialize in specific crafts and hence had to depend on others for subsistence goods. These goods were first exchanged by barter. Specialization depended on trade, but was hindered by the "double coincidence of wants" which barter requires, i.e., for the exchange to occur, each participant must want what the other has. To complete this hypothetical history, craftsmen would stockpile one particular good, be it salt or metal, that they thought no one would refuse. This is the origin of money according to Smith. Money, as a universally desired medium of exchange, allows each half of the transaction to be separated.[3]
For a few years now, the Preparedness Community has been pointing to the economic issues of Venezuela and asking the public to take a good hard look at what is going on.  Our hearts go out to those who are suffering, and at the same time, our minds consider what we would do if we found ourselves in the same predicament.  One thing that we can definitely learn is how the people have adapted and found ways to continue living.  One major way that the people are surviving is through creating a barter economy.
So as you consider items to stockpile, you should think about items that are necessary, but might not take up a lot of space.  Referring back to Mark Goodwin’s book mentioned above, one thing the main characters looked for were canning lids and rings.  They don’t take up a lot of space and in a real collapse situation, they will be really worth it!
An online swap meet of sorts, at Swap.com there is no bidding or money exchanged. Rather, you offer to trade the stuff you no longer want. You’ll then have the ability to choose from books, movies, CDs, and other items. The site doesn’t seem to have monthly charges, but you’ll be responsible for shipping costs associated with items you sell. Swap has its own free iPhone app for simple listing and searching.

Many prepper fiction novels eventually get to a point where there is a barter economy or the characters visit a Trading Post.  For instance, a trading post plays a prominent role in Mark Goodwin’s series, Seven Cows, Ugly and Gaunt: A Post-Apocalyptic Saga of America’s Worst Nightmare.  In the novel, the characters use silver to purchase the necessary items to survive and make life easier.  Goodwin’s novel is a post-apocalyptic EMP story.  The poop has really hit the fan in this one!
And that means everything from tuna to stamps to cigarettes has its own unique value in a trade and barter market. — Alexandra Cardinale, Vox, "Why ramen is so valuable in prison," 14 Nov. 2018 European officials were also looking at a barter system that would allow Iran to sell oil, for example to China, and use the proceeds from that sale to purchase goods or technology from Europe. — Laurence Norman, WSJ, "Europe’s Payment Channel to Salvage Iran Deal Faces Limits," 25 Sep. 2018 With unemployment around 9 percent and consumer prices surging, some Argentines are again turning to barter clubs, which first emerged during the collapse nearly two decades ago. — Almudena Calatrava, Fox News, "Argentines seek soup kitchens, barter markets amid crisis," 10 Sep. 2018 This particular search insired Gellar and Laibow to hop on the phone and barter. — Colleen Leahey Mckeegan, Marie Claire, "Sarah Michelle Gellar's Second Act? Disrupting the Food Industry," 18 Apr. 2017 Choco Pies became so prevalent for sale or barter on the streets that North Korea reportedly banned their import to Kaesong in 2014. — Brian Murphy, Washington Post, "The Choco Pie dividend: South Korean firms are drooling at the prospect of business in the North," 17 June 2018 In 1996, amid crippling famine, Ji tried to steal a few pieces of coal from a rail yard to barter for food. — Brian Murphy, BostonGlobe.com, "Could these outspoken North Korean defectors return home?," 11 June 2018 In 1996, amid crippling famine, Ji tried to steal a few pieces of coal from a rail yard to barter for food. — Brian Murphy, BostonGlobe.com, "Could these outspoken North Korean defectors return home?," 11 June 2018 Instead, like many early civilizations, they were thought to mostly barter, trading items such as tobacco, maize, and clothing. — Joshua Rapp Learn, Science | AAAS, "The Maya civilization used chocolate as money," 27 June 2018

Other countries, though, do not have the reporting requirement that the U.S. does concerning proceeds from barter transactions, but taxation is handled the same way as a cash transaction. If one barters for a profit, one pays the appropriate tax; if one generates a loss in the transaction, they have a loss. Bartering for business is also taxed accordingly as business income or business expense. Many barter exchanges require that one register as a business.
But the thing is, EVERY economy has collapsed at one point or another.  People who believe that it can’t happen in the United States of America are not critically thinking.  It is a possibility!   The economic fundamentals of the 2008 crash haven’t changed.  In fact, the Powers that Be printed even more money.  We are in even more debt!  Many say we have an economic system that is not sustainable.
No academics I talked to were aware of any evidence that barter was actually the precursor to money, despite the story’s prevalence in economics textbooks and the public’s consciousness. Some argue that no one ever believed barter was real to begin with—the idea was a crude model used to simplify the context of modern economic systems, not a real theory about past ones.
Especially prior to the Christmas holiday season, a gift and craft exchange can take the pinch out of your budget. Contact people within your network and arrange a day where people exchange homemade holiday decorations. You may not find everything you’re looking for, but you will likely find at least a few stocking stuffers – and the perfect price.
Barter-based economies are one of the earliest, predating monetary systems and even recorded history. People can successfully use barter in many almost any field. Informally, people often participate in barter and other reciprocal systems without really ever thinking about it as such -- for example, providing web design or tech support for a farmer or baker and receiving vegetables or baked goods in return. Strictly Internet-based exchanges are common as well, for example exchanging content creation for research.
So as you consider items to stockpile, you should think about items that are necessary, but might not take up a lot of space.  Referring back to Mark Goodwin’s book mentioned above, one thing the main characters looked for were canning lids and rings.  They don’t take up a lot of space and in a real collapse situation, they will be really worth it! 

Are you self-employed and tired of only having your pets to talk to at home? Visiting a new city and need to find a space to hold a meeting with potential clients? If so, LiquidSpace can help. Using their iPhone or iPad app, members scan through available work or meeting space, book the space for specific times, and get directions and access to other services that the space provides. The company is debuting in the San Francisco Bay Area soon, and they hope to expand nationwide quickly.
Barter exchanges have their own unit of exchange, usually known as barter or trade dollars.  Trade dollars or barter dollars are valued in U.S. currency for the purposes of information returns.   Trade dollars allow barter to take place between parties when one party may not have a simultaneous need or desire for the goods or services of the other members.  Barter exchanges act as the bookkeeper for keeping track of trade dollars that participants accumulate. Earning trade or barter dollars through a barter exchange is considered taxable income, just as if your product or service was sold for cash.
In his analysis of barter between coastal and inland villages in the Trobriand Islands, Keith Hart highlighted the difference between highly ceremonial gift exchange between community leaders, and the barter that occurs between individual households. The haggling that takes place between strangers is possible because of the larger temporary political order established by the gift exchanges of leaders. From this he concludes that barter is "an atomized interaction predicated upon the presence of society" (i.e. that social order established by gift exchange), and not typical between complete strangers.[14]
The Internet has provided a medium for new growth in the bartering industry. This growth prompts the following reminder: Barter exchanges are required to file Form 1099-B.pdf, Proceeds From Broker and Barter Exchange Transactions, for all transactions unless an exception applies. Refer to Bartering in Publication 525, Taxable and Nontaxable Income, and the Form 1099-B Instructions, for additional information on this subject. Persons who don't contract with a barter exchange or who don't barter through a barter exchange but who trade services, aren't required to file Form 1099-B. However, they may be required to file Form 1099-MISC.pdf, Miscellaneous Income. Refer to the Form 1099-MISC Instructions to determine if you have to file this form. If you exchange property or services through a barter exchange, you should receive a Form 1099-B. The IRS also will receive the same information. 

Economic historian Karl Polanyi has argued that where barter is widespread, and cash supplies limited, barter is aided by the use of credit, brokerage, and money as a unit of account (i.e. used to price items). All of these strategies are found in ancient economies including Ptolemaic Egypt. They are also the basis for more recent barter exchange systems.[17]
Bartering is the trading of one product or service for another. Usually there is no exchange of cash. Barter may take place on an informal one-on-one basis between individuals and businesses, or it can take place on a third party basis through a barter exchange company. A barter exchange is any person or organization with members or clients that contract with each other (or with the barter exchange) to jointly trade or barter property or services. The term does not include arrangements that provide solely for the informal exchange of similar services on a noncommercial basis.

In trade, barter (derived from baretor[1]) is a system of exchange where participants in a transaction directly exchange goods or services for other goods or services without using a medium of exchange, such as money.[2] Economists distinguish barter from gift economies in many ways; barter, for example, features immediate reciprocal exchange, not delayed in time. Barter usually takes place on a bilateral basis, but may be multilateral (i.e., mediated through a trade exchange). In most developed countries, barter usually only exists parallel to monetary systems to a very limited extent. Market actors use barter as a replacement for money as the method of exchange in times of monetary crisis, such as when currency becomes unstable (e.g., hyperinflation or a deflationary spiral) or simply unavailable for conducting commerce.