If you are an instructor looking for an open textbook to assign to your class, here are some resources for finding open textbooks.
BCcampus Open Textbook Project
This project out of British Columbia currently lists more than 60 open textbooks from twenty-four disciplines including Accounting, Biology, Chemistry, English, Math, and Psychology. Textbooks listed there can be used by anyone free-of-charge (digital versions) and instructors are free to make any modifications they wish to the text, as long a they attribute the source and, in turn, make available the revised work with an open license. Texts available through the site go through a peer review process.
OpenStax College is a nonprofit organization committed to improving student access to quality learning materials. Their free textbooks are developed and peer-reviewed by educators to ensure they are readable, accurate, and meet the scope and sequence requirements of your course. Through their partnerships with companies and foundations committed to reducing costs for students, OpenStax College is working to improve access to higher education for all. OpenStax College is an initiative of Rice University and is made possible through the generous support of several philanthropic foundations.
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. This pilot initiative publishes high-quality, cost-effective course resources by engaging faculty as authors and peer-reviewers, and libraries as publishing service and infrastructure.
Open Textbook Library
This library is a tool to help instructors find affordable, quality textbook solutions. All textbooks in this library are openly licensed.
Open Learning Initiative (OLI)