Available in English and in Spanish, InventBuy is a new marketplace that aims to let people purchase whatever they want, right when they need it and at the best possible price. Those who use the site are asked to fill out a short form detailing the products that they want to purchase, and that information is then forwarded to all the vendors who are registered on the site.
If any of these vendors has that item on stock, then he will get in touch with the user. They will be able to start negotiating the price, and if an agreement is reached then they will have a deal.

And if more than one vendor can provide the user with the item in question, then a bidding process will ensue. But at no point will any vendor know the exact price being offered by the others.

The site can be joined and used for free, both by buyers and by vendors. The former will actually be able to individualize as many items as they fancy when asked what they are looking for, and vendors will be allowed to have their own customized storefronts.
Web: http://www.inventbuy.com