[MiniOne]

I'd say a decent size for a banner would be 468px × 60px, though I'm not sure.
Jasper nice try though, that sort of banner wouldn't attract many players, I was thinking more of a sort of slideshow or animated banner. Though I don't know how to do this I've seen it done before.

If you guys would make me a few banners, I'd be happy to find some sites to place them on.

Also Steve Is right, advertising Zone as a single product is dumb, since Zone is part of a package. Though I would prefer making Zone player count grow more rather then another server.