Not sure that a "job shop consultant" will be your best avenue to professional development. For the business aspects, maybe some local college courses? For the mix aspects, there are several good books and seminars.
Most consultants want to specialize in businesses where a bit of insight can have tremendous leverage on their clients' business. Probably the worst fields to be in would be with small shops (only a few employees to leverage that knowledge), low upside (little of their own IP - just messing with other people's stuff), with a high volume but most everything a bit different, with some economic tides and competitive alternatives running against them, who might currently be struggling to stay pay their bills.
To put it another way, that description kind of fits a small dry cleaning business as well as other "shops" that might have come to mind. Now there are probably decent trade associations, forums, etc. on how to run a profitable dry cleaning business -- but maybe not the very smartest or most honorable consultants hoping to make a living off of you?
I'm sure there are exceptions -- likely among PM ranks who specialize in certain aspects. But I'd broaden my search for contacts, courses, books, interest groups, etc. Many towns also have something like a president's association, small business forums, etc. where you can make friends and swap idea with other business owners -- sometimes the most creative solutions come from someone with a slightly different perspective.
PM might also have a dozen Texas-based job shop owners who'd be interested in meeting up every now and then?
