Check out CHEGG.COM! They pay top dollar, on average $40 a book. They cover the shipping to send your books to them. And they plant a tree for every book sold to them!!!
Also, use promo code CC106510 and you guaranteed $5 extra!
Next semester, you can rent your text books from them and save a ton of money! I use it and I pay less than $200 on books. Again, if you use promo code CC106510, you'll save an extra 5%. This is a deal that can't be beat!!