Yeah, there are a bunch. If you mean shelf scale- what we used to call "solid models," there is a Yahoo discussion group. Go to yahoo and in their search engine look up discussion groups and then search either solid models or scale models.
For flying models I do not remember a specific group but several years ago I did a Google search and found numerous sites about balsa flying models. One site you certainly should look at is Penn Valley Hobbies. They specialize in balsa rubber powered models, including a nice selection of repro kits. There is also the SAM, Society of Antique Modelers or something like that. They tend to specialize in engine powered models, though.
Other vendors include Easy Bilt models that has an extensive line.