I have lots of textbooks that have to be thrown after I graduated from secondary school and college. Luckily my cousins can use some of my textbooks, at least they can help me to clear my store. Anyway, if you think you want to sell textbooks, then you can visit SellBackYourBook.com. They are a best place to sell back your used books online. What you do is just enter the ISBN then you can sell your textbooks online.