If you are any where near Michigan , Bill Schwab and Joe S (sorry Joe , don't want to spell your last name wrong) have both taught beginner workshops and they are very patient and levelheaded in their approach.
I have seen them in action at photostock, as well Bill has taught at Steve Shermans and as well at Gallery 44 here in Toronto with nothing but praise of his teachings.
I'm in Florida. I would love to attend some sort of workshop or receive some kind of instruction, but I can't find anything around here like that. So it looks like I'm now in the market for a 4x5 camera.