The SF SPCA is highly regarded for churning out very knowledgeable trainers and is based in positive reinforcement/operant conditioning/classical conditioning, etc. methods. Basically, no physical force needed. Plus, you get to work with Jean Donaldson!!!

http://www.sfspca.org/academy/index.shtml

I figure if you're thinking of AZ, CA isn't too far away You could just come for the Academy and then move back to AZ. Also, there's the Canine Behavior & Training Academy of the Marin Humane Society with Trish King:
http://www.marinhumanesociety.org/Behavior/CBA.html

Also, check this page out:
http://www.apdt.com/po/career.aspx

If you can't find a school, find a GOOD trainer and apprentice under them, go to conferences, read, study, and always keep an open mind.

Also, try to get some titles on your own dog. Titles are like a dog trainer's credentials, almost =)