CHEST is in Chicago, and is run by TickleChgo. There's a forum here for them.
The next closest event for a Chicagoan is MidWest NEST, which also has a forum here. It's in Columbus, OH, and is run by Bellarisa.
From Chicago, you can also attend either coasts activities with equal costs. Like TTD said, that includes the soon-to-be-happening NEST, in Philedelphia, as well as TTD's Hyena's club, on the East Coast, held in a number of eastern-seaboard states, and the West Coast Gatherings, held in California and Oregon, primarily.
Hope you find one you enjoy!
dvnc