I did my training in Phoenix yeeeeeaaaaars ago so not up to date with specifics in the area. BUT, going for a smaller "FBO style" school is ALWAYS cheaper and MOST of the time offers what you need to pass your FAA checks and that's all that matters in the end. You don't need fancy brochures and 25 different books and book packages that explain the same thing in 20 different ways. This was true 15 years ago. This is true today. Do you really think a commuter / 135 operator cares if you have done a fancy "airline program" or if you've done it with an FBO? I don't think so. What does matter however is that you know what you are doing. So go find yourself an FBO that gives you a good feeling (ie they will not screw you with overpriced aircraft that are not maintained properly) and can provide you with an instructor who seems to care about what he or she is doing and is not only in it for building hours.... Or.......
You do what "I Love Lamp" suggested. Find 5 or so guys in the area who are looking for an aircraft for hour building and training, then post here for a couple of instructors who are looking for work. Once you have a group of people you feel you can trust you go out and buy an aircraft together. This has got to be the cheapest way to do it and it would be fun too!