By Chris Lesinski, Lifehacker
You can buy them online from hundreds of Web sites, share them with friends or spend $600 (seriously—that's the average) at the book store. If you're committed to saving serious cash, you can also spend $0 on books this semester.
One caveat—I'm not going to B.S. you with dreams of open-source and digital textbooks, despite how nice they sound in theory. I don't know what university you go to, but at mine, that's not realistic. My professors use AOL.
Every university has a stockpile of free books: the library. Depending on how irresponsible you are, you might never otherwise enter the library, but this should be your first stop during textbook season. It is the crux of this whole concept.
First, you have to find your book at the library, which requires a surprising amount of creativity. At the basic level, novels and famous works are easy. When you get into very specific textbooks, it gets harder. The first thing you should try are the intercollegiate book sharing networks; they put hundreds of libraries in your range for free. Libraries frequently get textbooks as part of a donation, and they're not going to burn them (unless Follett pays them enough money).
Next time you see books that seem obscure, like 'A Communist Anthology of Native American Poetry" or "The Children's Compendium of Short Stories About Pregnancy," know that you can find the material elsewhere. Selections, collections and compilations are filled with re-packaged old content—another tactic of evil publishers. Even books like "Freakonomics" and "The World is Flat" are mostly made up of old material. At the library, you can use online databases or other compilations to piece together your own version of the same book.
You'll also have to fudge the editions. The most recent edition of your Conjuring 101 textbook won't be at the biblioteca. Publishers make miniscule changes in a book so that they can release a new edition each year and make more money. But that means that normally you can get through 92nd edition classes with a 2nd edition text, since the changes are often subtle: page numbers are shifted, chapters are switched, etc. The best way to wade through an old edition is by looking through the table of contents and finding the old version of the new topic you're supposed to read on.
If it all fails, hit up the research/reference desk where your school probably employs a lackey whose sole responsibility is to find material for you.