Do I really have to get the textbook?
Technically, no. You also don't really need to pass the class. Whether you buy the book or not, you are responsible for the class material.
I believe you should get the textbook listed on the syllabus. If you choose to buy an older edition be aware that even though the material may not have changed a lot, sometimes chapter numbers do. Whichever edition you get, you are responsible for the class material.
Do I really have to get the current edition of the textbook?
Check the school library and the reserve desk. If I (and many other teachers) have extra books I (we) will usually put one on reserve for library use. If they don't have one, let me know.
What if I just can't afford to get the textbook?
You can: A) keep it for future reference (I recommend this), B) sell it back to the bookstore for a few bucks, or C) sell it online for a few more bucks (I recommend half.com)
What do I do with the textbook when the class is over?
I'm not sure. It does seem like a money making venture for someone, I'm just not sure it's the student who makes out the best.
Should I rent my textbook?
CourseSmart is a place where you can purchase access to electronic versions of textbooks for a limited time. the price looks good but there are some crawbaks. Thay also offer chapter 1 free for some textbooks.
What about CourseSmart?