I ran across this site on another homeschooling site. http://www.homeschoolbookrenter.com/main.sc They have MOH, Shurley English, Saxon Math, Exploring Creation Science and many more titles. You rent the books for a 9 month period. Its looks pretty cool.
I looked at the prices. Some of them I can buy used for almost the same price they rent for. For example, Apologia General Science they had for $38. Homeschool classifieds had it ranging from $35 up. Great Science Adventures is another I'm not sure would be worth it.