It will never cease to amaze me how much publishers charge for a school textbook. Don't they realize just how poor most college students are? I was very poor and dreaded buying books at the beginning of each semester.
Instead of racking up additional debt just for some books, turn to your best friend, that is, the Internet, and purchase used text books. So long as you verify the book is identical to what your professor requires, and it's in good shape, what does it matter? Plus, who knows, maybe the previous owner used the book to take exceptional notes in the page margins. Bonus!
Amazon is a staple on any decent book list, I would think. Amazon has a collection of new and used books that reaches far and wide, and a Prime Student membership that sweetens the deal. As with most used textbook services, Amazon promises savings off books ranging from 40 to 90 percent depending on the book and condition.
Chegg offers more than a method of purchasing used textbooks. Students can also sign up for tutoring, or ask for help with a homework assignment directly on the site. Forget about the extra help for a moment; let's get back to saving you money. Chegg appears to have a magical potion to lower the cost of textbooks beyond reasonable expectations. In one instance I found a used book priced at $27.53 on Amazon listed on Chegg at just $4.99. The new price for the same book currently sites at $242.55 (again, on Amazon).
Half is owned by eBay, but it doesn't take the same bidding approach to selling you textbooks. Although you do have to purchase items directly from other Half account holders, instead of the website directly. Doing so allows users to set a price for the book, often resulting in lower prices. On the other hand, a user can easily fib about the book's condition.
BigWords is a service unlike those just mentioned. In fact, the site doesn't even sell books. But it does allow you to search for a book across some of the sites I just mentioned (plus others). The results are displayed with the lowest price available after taking shipping costs and coupons into consideration.
Just so I can sleep with a clear conscience tonight, I need to include a brief disclaimer. Before purchasing a used textbook, double-check that you're ordering the correct edition by matching up the ISBN number. If you have any doubt about it being the right book, triple-check with your professor.
There's very likely to be more sites and services who provide just as good, if not better deals than what I've mentioned here. If you have a favorite one, be sure to let your fellow students know in the comments below.