I don't think there's a better resource for this than YouTube. There's so much info available out there. My suggestion would be, watch a bunch of tubers stuff and then ask blokes on the forum more specific things like "where to buy raw materials" etc.
My experience in building top water poppers and plugs was all learned from the search tool here (and a few other forums) and from YT. But I did ask (and was helped) specifics like where to buy stainless wire etc.