OPTION 1: UW Bookstore. Sometimes this option works well, and sometimes it doesn’t. When it doesn’t the other options might be better for you!
OPTION 2: U-Match.net. Buy and sell textbooks for free. Also sell whatever you want on the classifieds, and form study groups on the class message boards.
OPTION 3: Boughtback.com. Something different, sell your textbook using an online auction. Who knows how much you might be able to bring in for your textbooks.
OPTION 4: Cheapswap.com. Sell your textbooks and other things on cheapswap.com!
OPTION 5: Ebay.com, Amazon.com, Half.com, Powells, All Book Stores. Of course there is always the option to play with the big boys and sell on the large sites. Problem is you have to deal with shipping.
What is really cool is that options 2, 3, and 4 are all done by UW students and started on the UW campus. So check them all out and use them all to help get the best money for your textbooks! You can also read more about some of these options HERE.