It may be further than you want to drive, but the Urban Knaves of Grain (http://www.knaves.org/
) is located in the west suburbs.
Details on on the website, but their regular meetings are at the Rock Bottom in Warrenville, just off of I-88. They also hold monthly "tech sessions" at another local establishment and monthly outings/events/activities (pub crawls, group brewing sessions, summer picnic, etc.). They are a fairly large group, with a wide range of experience levels.