Summerfest? Please! Talk about overpriced and not worth the money. I agree with Duffman – all the block parties around here are sweet – I can't wait till Locust Street Days – thats' a fun one (lot's of interesting people watching).

Wisconsin weak? Here's a short list of motorsports activities:

GLD (mentioned)
Road America (June Sprints are sweet)
Autocross at Miller Park
www.w-a-g.org (Wisconsin Autosports Group; they put on rallycrosses, and road rallys)
Highway 100 (yes, it's pouserville, but it's still something)
Chicago isn't that far (as mentioned; HIN, Import Rev)
Milwaukee Burrito Meets ()

It's a hell of a lot more than where I used to live (Minneapolis/St. Paul, MN). There wasn't a track within 1.5-2 hrs. of the Cities (Rock Falls Raceway in Eau Claire).

I think Milwaukee has a lot better "car culture" than many other cities. No, it isn't SoCal, but it's still not bad.