I would recommend...
Divers Den
Since this shop is in Lake Orion, it is pretty close for you. Dave, the owner, is a great guy and an excellent instructor. The shop has a dive club called "Descenders" that meets the first Thursday of every month at 7pm at the Hamlin Pub in Lake Orion. If you stop in say "HI" from Mike!
If you don't mind a bit of a drive...
Great Lakes Dive Center
This is a very good shop. The shop is well stocked for anything you could want. The owners are also great people. They will go out of their way to make sure their customers are happy and taken care of.
Also...
Brunos Dive Shop
Another great shop and well worth the drive. One great thing about this shop is that they have their own dive boat. This means that your open water checkout dives can be out on the boat diving shipwrecks. How cool is it to be doing your checkout dives right next to a historic shipwreck. Also, the crew is amazing as well.
One shop I WOULD NOT RECOMMEND...
US Scuba
I unknowingly took my open water class at this store. Things at this store seem to be overpriced and the shop is focused on training divers for warm water trips. The shop does nothing to teach about diving around the Great Lakes. The shop doesn't even stock drysuits. When I was in my class and asked about diving around here, I was told that there was no reason to dive around here.
If you have any questions, feel free to PM me. Id me more than happy to help.