T/O,
No particular reason to base yourself in AZ over CA. The reason I based myself there was because of the flying school. I was looking for somewhere where I could rent both a tail-dragger and a twin, and I came across
Chandler Air Service, who not only have Cubs and a Husky for the tail-dragger flying and an Aztec for the twin flying (as well as loads of PA28s and a couple of C172s), they also do aerobatics, they have an Arrow which was useful for some of the longer trips, and I was very impressed with the overall attitude when I spoke to them on the phone (for about 1/2 hour).
They lived up to all my expectations - the instructors are some of the best, the checkouts are the most thorough I've ever heard of, and aerobatics are always taught to competition standards.
Phoenix itself is a nice place to live, although there's not a whole load there for tourists to do. That might suit you - you might prefer to fly to the touristy places rather than base yourself there.
As for the Visa Waiver, this has absolutely nothing to do with flying. Everyone who enters the US for any reason needs a Visa. However, for citizens of certain countries, the authorities have waived this requirement, and will allow you in under the Visa Waiver program, for a maximum of 3 months, providing you're not working or studying in the US. It doesn't cost anything, and it'll happen automatically as long as you have a passport from one of the appropriate countries. But you will still need to get your FAA pilots license sorted out if you haven't already (and it might be a bit late now if you're planning on going in a couple of weeks...)
FFF
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