Most of the photo shops here in Southeast Michigan have closed down. I believe Huron Camera in Dexter still sells darkroom supplies. I would check there first as I believe Big George's in Ann Arbor closed their photo section. I believe all the Adray's around town closed as well.
Adray's in Dearborn was my favorite place. I bought my 4x5 Toyo there and all my darkroom supplies. They closed after I had moved away. What a shame!