A few other things to check out...
There is a Bud Harris Cycling Oval that has racing events.
http://www.acaracing.com/home.html
Riding down there is kind of a drag since it is on Washington Blvd. You might be able to put your bike on the bus rack and do practice loops once you're there. It's a great traffic-free (except for getting there) practice spot.
There are other group rides that leave from the city: Major Taylor rides from the South Side on Wednesday evenings and the Flock of Cycles (slower paced, short ride but a good way to meet a bunch of other cyclists with a variety of skills/interests). You can find both of those by checking the calendar on this web site.
Bike fest is coming in August -- that will have a ton of rides.