Welcome to CC and to the larger AFOL online community. You should definitely check out MichLUG (Michigan Lego Users Group):http://www.michlug.org/
They seem to be a pretty active group, and I've seen pictures of some pretty impressive group displays they've done in the past. At least a couple of members are also here on CC. From looking at their webpage, it looks like they've got a display at the Henry Ford Museum for the month of December, so that's in your area.