I could not find out if there are outstanding todos that I could assign myself to as a newcomer. I'd like to contribute, but don't know where to start. Is there an issue board somewhere with missing books, or something else?
First-time contributors should select something from the appropriate section, because that gives you the greatest chance of succeeding and the least burden on our reviewers as you get started.
Our toolset has a help wanted section and some outstanding issues: https://github.com/standardebooks/tools#help-wanted