Look up the book on websites like Half.com, Bigwords.com or Mycollegetextbooks.com. Websites designed for textbooks or books at discounted prices often have surprising deals and comparison options.
Compare the prices of books. The different websites will have different costs and prices listed. Look at the lowest and highest costs; comparing the cost is one of the easiest tasks because the websites list the prices directly.
Look at the section determining the condition of the textbook. Many websites, like Half.com, have books listed according to "new," "like new" or "used" which give an idea of the condition of the book. For example, a new book is a book in good condition or never used while a used book might have stains, tears or other problems.
Read about the merchant or seller. Discount books are sold by a variety of sellers, including individuals selling used books and book dealers that are giving discounts on new books. The main keys to watch when comparing merchants and sellers are methods of shipping and their online reputation. Merchants or sellers who have no or very few complaints and who have executed several transactions are usually the best options for good quality products.