Well, I have a friend who lives in St. Louis that started an audio club out there. I think they call it the Gateway Audio Society. They have a dedicated discussion forum on Audio Circles. Here's the link: http://www.audiocircle.com/circles/viewforum.php?f=70&sid=62f27250d94010363be3def14e707177
There's maybe 7 or 8 regular members and probably a few other less frequent participants. They generally meet whenever a few of them have time and someone is willing to host at their home. When they started they were meeting every other weekend (at least that's the impression I got from my friend's emails), but now I don't think they meet that often. They go over the host's house, bring some equipment of interest, have a few beers, some munchies, listen to various components that the members have brought and talk about, well, audio stuff. Later, they will post remarks and pictures of the meetings on Audio Circle. Just one example of how a club can work. I'm sure there are bigger clubs and smaller clubs with different variations of goals and how they meet. Personally, I like the way the Gateway Audio Society does it as I am most interested in hearing different components and equipment. Any other thoughts?