There are an overwhelming amount of open textbooks and other OER available for professors to use as-is or remix to fit the needs of their specific course. Happily, the University of Minnesota has created the Open Textbook Library, a searchable collection that include extensive reviews that help faculty determine which is the best book for their class. Want to help? Contact UMN to become a reviewer yourself.
The College Open Textbooks Collaborative, which emerged from the Community College Consortium for Open Educational Resources, includes “twenty-nine educational non-profit and for-profit organizations, affiliated with more than 200 colleges.”
Their website offers a list of open textbooks and other open educational resources by subject. They also offer peer reviews of many open educational resources, to assist faculty in choosing material for their courses.