Got my Glock from Loan Wolf in Glendale, AZ:
http://www.lonewolftradingco.net/ I believe they supply to law enforcement. By far the cheapest Glock dealer in town.
Of course - depending on when you are heading here we have the BIG ASS Crossroads Gun Show in town on 19th Ave / McDowell at the Phoenix Fairgrounds on 24th / 25th Feb. Hundreds of vendors from all over all under 1 roof - deffinately a good chance at a deal there too.