As I'm a white guy, I can only offer hazy memories of location, but what the hell, it's a starting point.

There are two that I remember in the Winter Hill area, close to Foss Park (the only name I remember is Curlz and Cutz, not sure if it's still open, I seem to remember they also did fur storage). I remember another in East Somerville, close to Sullivan. I believe there's also one on Highland, up a bit from Davis, but I don't remember the name (I do remember it was a beauty supply store as well).

Good luck!