Also a fellow mapster. The annual meet is Oct. 3-4 in Hammond, IN. Room-to-room is at the Amerihost Hotel, and the Expo is at the Jean Shepherd Center on Saturday morning.
It's great fun. You'll see maps you never dreamed existed.
My site doesn't show up very well in the Google results, because I haven't had time to update in awhile. http://home.comcast.net/~jschlesser3/ .
Enjoy!