Not sure where you are traveling from but if you will be coming up 75 through north west Ohio you have to stop in at Jaquas in Findlay, Ohio. Well worth a visit and there are few places in the US that compare. (they are about an hour and fifteen minutes south of Dundee)
In SE Michigan, there are really few shops that are worth a special trip. Michi-gun in St. Clair Shores is ok. Not a ton of inventory on the racks but they have some good guns in their back room and in their safes; Williams shop up in Davidson (45-60 minutes north of Detroit) can be a good place to look. Some of their used guns appear to have been used beyond any reasonable life, but I have made a couple of good finds there. If you are in the mood to be degraded, abused and be talked to like you are too stupid to own a gun then Guns Galore in Fenton is just the place for you.
Safe travels
