If you don't find OER that is useful for you, you might consider modifying a current OER to meet your needs or authoring a completely new work. The resources below may help.
After you have created a new work or modified a work or works substantially, be sure to submit it to Scholarworks@UA, our institutional repository, and let D'Arcy Hutchings know so it can be added to the Textbook Affordability Heroes page.
Note that UAA Information Technology Services or Faculty Development & Instructional Support (for UAA faculty) may be able to help provide some of the technical support you may need to modify various OER files.
There are many tools you might use to create or revise your textbook or other course materials. Common ones include Pressbooks, Manifold, and LibreTexts. Which tool should you use? Consider referring to this tool comparison table or this comparison page (note that neither of these include LibreTexts).