I had a Jimmy L class last year. Very good. Excellent training.
Another alternative:
I've gone to http://motoventures.comin Anza, Ca 4 times (1 trials, 1 dirt bike and 2 big bike training days) in the last 3 years. It's close to San Diego, less expensive than JL, great venue / exclusive riding area (not training on an open lake bed with local traffic zooming through..) I can't recommend enough the value of this outfit, Gary LaPlante is an extremely talented rider and coach. In fact, he wrote a book on it, check the website.
Cheers