g:transistor cpu logisim
https://mrmcsoftware.wordpress.com/2017/03/07/testing-and-improving-my-cpu-design-with-logisim-and-digital-logic-basics/
I’ve found a few by reading posts on the Logisim reddit page: https://www.reddit.com/r/logisim/ but it would be nice if there were more sources. If you want a few of the ones I created (or modified) go to: https://sites.google.com/site/mrmcsoftware/home/downloads skip the non-Logisim stuff (Logisim stuff starts at cs3410*)
https://sites.google.com/site/mrmcsoftware/home/downloads

Clock.circ
https://www.reddit.com/r/logisim/
..
https://www.reddit.com/r/logisim/comments/8iokkj/exi_made_a_user_friendly_24hour_clock_all_parts/