The Unseen Servant forums

Teramis Christian, a long-time member of this forum (though she doesn't have time to play these days), wrote a small guide a while back called The Gazetteer Writer's Manual. I won a copy of it and have used it, but haven't actually sat down to write any kind of review of it.

Fortunately, Game Knight has! You can read his review of it HERE.

If you are a closet writer and have your own little world you're trying to flesh out, this is a great resource for doing so.