Open Textbooks — CAUL: Finding open textbooks

Athabasca University Pree - free pdf and low cost print version of mainly Canadian books.

BC Campus open movement including textbooks.

Advocacy, training, and links to college level open textbooks and other courseware.

Content Commons of free, open-licensed educational materials in fields such as music, electrical engineering and psychology.

Access to teaching and learning materials in the STEM disciplines (science, technology, engineering and mathematics). Search by level, resource type, and subject.

Worldwide learning network of shared teaching and learning materials.

Collaboration of higher education institutions to share and expand their open course offerings.

Peer reviewed post secondary textbooks

"Open SUNY Textbooks is an open access textbook publishing initiative established by State University of New York libraries and supported by SUNY Innovative Instruction Technology Grants".

Free to read versions of the texts at Flat World Knowledge

Wikimedia's community for creating and sharing educational textbooks.

HathiTrust is a partnership of major research institutions and libraries and their "aim to build a comprehensive archive of published literature from around the world . It provides long-term preservation and access services for public domain and in copyright content from a variety of sources, including Google, the Internet Archive, Microsoft, and in-house partner institution initiatives."