There have been several books written on creating addons for WoW (I don't think anyone got rich from them) and much of the basic information in them is still relevant although somewhat geared toward XML (also still viable).
gamepedia is probably the better resource for up-to-date API information.
FrameStack is a useful tool (even more so these days with
FrameStackGlobalizer because stuff happens)
I haven't seen any questions so I'm not sure where you asked unless they've been generic "show me how to make an addon" type questions. Specific "Tried/trying to do this and got these errors/funcky results" with some code tend garner more responses because the possibilites of things you can do in wow are huge and general questions tend to require book size responses.
Just because it's a game many assume that addon creation is a simple prospect. Apart from other addons, one of the <cough>basic learning tools/sources of information is the Blizzard UI itself. You can
extract all the UI code that makes up the stock UI and "see how Blizzard does it".
Blizzard is also documenting parts of the API see /api in-game (it's better with
this)