Here in the forums?
Go to the forum for the particular game you are modding. Skyrim for instance: https://forums.nexusmods.com/games/page/1-welcome/
Along the top, just under the title image, there are links to all the sub-forums. Including the Creation Kit and modders forum: https://forums.nexusmods.com/forum/8921-creation-kit-and-modders/