The Metafinder - Although there is no comprehensive way to search for open course materials, this tool (from George Mason University) provides a one-stop search of most major repositories, including OER Commons, OpenStax, and BC Commons.
OASIS is a meta-search engine of 97 OER sources developed by and provided by Geneseo-SUNY.
Open Access Digital Library is a directory including more than "12,000 journals from over 80 databases. All content is free to the end user. The best way to use this site is to search by name for a particular journal."
JSTOR's Open Community Collections feature Open Access primary source materials in a wide variety of subjects contributed by libraries, museums, and archives.
OpenStax is part of Rice University, which is a 501(c)(3) nonprofit charitable corporation. OpenStax publishes peer-reviewed, openly licensed college textbooks that are free online and low cost in print.
Open Textbook Library is a multidisciplinary curated list of open textbooks. It is a great place to find best-bet texts in your discipline. The standards for inclusion in the Open Textbook Library are that the book must be available to download at no cost and/or printed at low cost and that it must be used at multiple higher education institutions; or be in some other way associated with an institution, scholarly society, or professional organization. Additionally, many of these books have been reviewed by faculty to assess their quality.
Springer Open is a repository of open-access journals covering a wide range of disciplines.
Library faculty members are happy to help you find OER for your courses. Please contact your library liaison to discuss options.