The schutzhund club that I belong to regularly brings in teachers, trainers, judges, training helpers, etc into our area for seminars. Same with several of the other organizations I belong to. All it takes is a willing teacher, and some coordination to put together your own seminar. Some teachers look for a stipend, some do it for the love of teaching and the promotion of the subject. Get enough folks together, come up with a tuition fee, a place for the instructor/s to stay and travel costs and viola. Your very own seminar. By cleverly promoting the event and making sure you keep group sizes to effective, working sizes (40 guys packed around a table to watch 1 guy paint frankly sucks). You can have a pretty effective working weekend with everyone walking away with something. If you think you're really going to get some good turnout, bring in a couple of instructors and structure the weekend around both. Allowing them to split groups and exchange information offering a variety of techniques. Or bring one in to sculpt, one to paint.
If you're not willing to do it on your own, approach one of the local clubs and see if they want to help out with something like this in conjunction with a contest.