@Maenad hm, from the little i know: you could try searching tumblr for your fandom + prompts, kinkmeme, fic exchange etc, there are many who collect prompts and encourage you to submit fills (as ao3 links or just tumblr posts). tumblr hides nsfw blogs from search if you're not logged in.

in case of femslash, maybe this helps: http://femslash-friday.tumblr.com/resources

& fanlore has at least this list, probably more that i didn't find: http://fanlore.org/wiki/List_of_Kink_Memes