Why are textbooks so darn expensive??

I made it through my second day of classes and, like my two previous semesters I am lamenting over the cost books. The thought of shedding out over $200.00 for books is ridiculous.
Something has got to give here.
Schools need to adopt a rent-a-book system where u can rent a textbook for the semester.
Hmmm....I think I need to put a bit more thought into this and come up with a plan.