I've been in Chicago for about ten years now and have always just ridden my mountain bike. Since I've finally come to the realization that I'm only ever going to ride concrete, I'm trying to decide on a lighter/faster bike. I ride primarily to work... around 7 miles roundtrip per day. Here's my problems:

A. I'm 6'6". I rode a 24" Trek MTB for a decade... and it was just a little too small. Every bike shop I go to doesn't have anything over 60/62cm. I'd like to hold out for 66-68cm ... but no one has anything I can test ride.

B. My old Trek just got stolen. My max budget is around 1000, but if I'm going to lock up a bike downtown / out in the open a lot?

C. Can't do fixie... my knees aren't very good.

D. Don't know if I can do road bike. I've looked at some used road bikes on Craigslist... but I don't like to be hunched over. I am seeing quite a few large road bikes on Craigs. Also, I always assume I'm going to get doored, so I like to keep my fingers on the brakes at all times. Would a "bull bar" be good for this?

Any help appreciated. My biggest need is to find some place where I can test ride big frames in Chicago.