College books, costing an arm and a leg!

So today I went and bought all but two of my college books for fall semester. I'm taking 4 classes and of course every class has new textbooks so I can't buy used ones. I just bought a math textbook last semester and had they not changed to the new books I could have used it again. Look at how these books cost:

English: 57.25 and 5.99

Medical Terminology: 97.75

Biology: 151.25

Math: 130.00

Its INSANE what they charge for books! That is like a weeks pay, or a car payment. I was really shocked, but I know that its only going to cost more. The good thing is that my sister is a semester ahead of me so hopefully I'll be able to use some of her books too.