The easiest places to sell your books online are also where you’d probably go to buy them. Amazon’s Sell Your Books program is mostly meant for textbooks, but does let you sell other books. FYI: The few remaining textbooks I have from school ended up selling to Amazon for more than all my other books combined.
Sell Your Books was easy to use, and I managed to get Amazon to accept about half of the books I owned. (Note: If a paperback edition of your hardback book is out, you’re usually out of luck on selling the hardback.) The prices on Amazon’s service were also comparable to, or slightly better than, those I found on other services.
Half.com also has a buyback program that focuses on textbooks. Their prices for my books were similar to Amazon's, and the site said it would accept a wider selection of my books.
I used BigWords, which pulls pricing data from a dozen or so retailers. The service also lets you enter multiple ISBN numbers so that you can check prices for multiple books in one search.
Before using an untested book buyer, though, check out the details--you might end up paying more for shipping than you make from its higher listed price.
Amazon will pay for you to ship your books to it, and Half.com offers a significant reimbursement that should cover the cost of shipping for most books. However, smaller operations may not have the same policy.
Either way, don’t expect to make a huge sum off of your book collection. Depending on what you have in your library, you’ll probably make enough to offset the cost of replacing the paper versions with ebooks. But unless you’ve got some rare first editions lying around, you're unlikely to make a hefty profit.
What to Do if You Can’t Sell Your Books
Even with a site like BigWords, some of your books just aren’t going to be worth the effort to sell online. If they’re still in relatively good condition, however, you can always donate them. It’s probably still easier for most people to donate books to their local library, or to Goodwill, the Salvation Army, or other local charities.
The Wisconsin Department of Public Instruction has put together a handy list of library agency websites nationwide if you need to know where to go to donate locally. If the list doesn’t have a nearby option for you, and you think you’ll have trouble finding a convenient place to donate, several charities accept book donations by mail.
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