The replies to this discussion has me wondering what those who have replied know what is going on in Chicago. Half of those who have posted don't seem to reside in Chicago, so how to know what is possible!?!
So no, Chicago does not have a one stop shop for all things bike, but I don't think that there is such a place anywhere. Northhampton does have a cool bike project that is doing a lot of cool things but I'm sure that it could not be compared to the amount of bike activity in Chicago that goes on between several organizations such as Active Trans, Working Bikes, Bike Winter, Cycling Sisters, the Chicago Cycling Club, Loaded Bikes, Critical Mass, the chainlink and others, not to mention West Town Bikes that has events/classes/workshops every day of the week every month of the year.
Also, one of the founders of Pedal People, Ruthie, got her start wrenching at Uptown Bikes (Urban Bikes back then) where she was introduced to bike trailers.
It's great to find out what good stuff is going on all over the world through the internet. That shouldn't be used to dismiss what may be going on outside of the front door because one has yet to simply step out and find what's there.