(1) If it happens you're going to be in Tucson on March 2, there's a humongous flea market/swap meet at the Expo Center. Over 400 tables! It's called the 26th Annual TMAC Toy Show. Lots of models and toys and everything in between.
(2) HobbyTown USA is a well-stocked model kit and R/C store with outdoor R/C track. Good people. 3700 E. Speedway Blvd.
(3) Ace the Hobby Place is a large, super well-stocked, model kit, supplies (including some aftermarket) and train store. Lots of paint and exotic supplies. It's attached to one of the most spectacular hardware stores you'll ever see! NW corner of 22nd Street and Kolb.
PS: If you run out South on Kolb a little ways, you'll find the Davis-Monthan AFB mothball pastures. Acres of 'barn find' military aircraft waiting for second careers.
Certified Good Guy Moonlight Modelers - 19 years Cactus Car Modelers - Charter (Founding) Member - 13 years