G'day and welcome to fanfic ozhater1 ... and may I say, that would seem a very insightful screen name.
You are correct in posting here: technically, The Writer's Lounge is where any non-story thread would belong. In other words, unless you are posting a story - fanfic or otherwise - you should post in this subforum.
Now, it's good to hear that you are interested in writing a fanfic. We always welcome new fics and new writers - variety is what keeps the forum alive. From a moderator's point of view, there is no problem with you asking for other people to think of ideas; as a writer, though, I have to say that it seems awfully unimaginitive. If you are really interested in writing your own story, surely you would fully invest your own imagination in it? Thinking up names, characters and line-ups is a very enjoyable aspect of writing a fanfiction; to pass that on to other people who are not writers of your fic seems at best indifferent, and at worst, a disservice to your fic.
That is all I will say on the matter, as you are, of course, well within your rights to ask for help from other fanfic members; and I am sure there are many who would be willing to help - there is nothing wrong with that. But as a fellow writer I really would implore you to take some initiative and try to dream up the setting and character details yourself.
In any case, I do hope you post the story here soon. If you have any further questions on this matter, or about fanfic in general, please don't hesitate to PM me or one of the other mods.
Cheers!
- Gavin.