Chegg.com offers options to rent textbooks, buy textbooks (new & used), or sell back used textbooks.

Search multiple sites to verify and locate old, rare, and out-of-print books.

A comprehensive book search engine that includes 30,000 new and used book dealers and databases to find over 50 million new, used, rare, and out of print books

Used, textbooks, rare, and out-of-print books from a global network of independent booksellers.

Another network of used bookstores and rare book dealers, which includes free shipping on larger orders and special services for librarians and collectors.

A network of used bookstores, listing over 28 million titles for sale.