What references and/or examples do you recall being the most useful as you transitioned form Obsidian User to Obsidian Plug-in Author? I have some really basic

What references and/or examples do you recall being the most useful as you transitioned form Obsidian User to Obsidian Plug-in Author? I have some really basic html pages and cgi scripts I'd like to port in as a plug-in, but haven't sat down with it yet.