Who in the area for Technical diving?

[68raggtop]

As my interests have been shifting towards tech, I am looking for information on what resources are available int the general area.  What shops, groups or instructors go beyond recreational diving?  Feel free to plug yourselves and others.  I am asking about training available, equipment sales/service, mentoring, groups, clubs, associations or any other people/places involved. 
Dave
(If it helps, my goal is Great Lakes wrecks.)