All officially released add-ons, plus some bonuses, are available as "all_supreme_worlds.zip" on the itch.io page.
Unpickled is an automatically generated database of worlds, levels, and secret locations from Supreme with Cheese. Click the links above to see more. It is inspired by an earlier project of the same name by AtkinsSJ.
Looking for tips, tricks, and hints on the editor and other aspects of Supreme? Check out Hammered's awesome Player's Guide to Supreme with Cheese.