I live right in your area. A fair number of technical divers in our area have learned from Rick Kruzel (can google his website online - Great Lakes technical diving). He's private and not associated with any shop. Extremely professional and flexible and will work around your schedule to get a course done (I have a very inflexible schedule and he planned all the dives with me over a month to get them all done in a non continuous fashion to allow me to complete the class within my schedule). Also a great teacher. Answers emails promptly if you want to contact him. I was the only student in multiple classes I had with him and was the same price as if it was a "full" class.