Aaaaahhhhh - now I get it.
Well, there is quite a bit to do here. Depends on if you want to keep it strictly car-related or not.
If it's only car stuff you're after, sounds like you guys have a big time planned at the track. There's also the Pavilions mentioned above. That's in Scottsdale (NW part of Phoenix metro). You could also set up a group dyno at StreetFlight (the place making the Duratec turbo). We have enough tracks around here to keep things pretty busy.
If you'd like to step out of the car world for an evening or two, your options increase drastically. There are a ton of clubs scattered around. I haven't been to Mill Ave., but I hear it's full of clubs, bars, etc. and you can actually bar hop just walking down the street. There are malls, but I'm not much of a shopper, so I can only tell you where they are. Of course there's the more "adult" side of things. Strip clubs abound here (though most call themselves Cabarets). We have our fair share of microbreweries too, but Po-Jay could probably give you more details on those. He's the beer guy here
October's a good time to come out. The temps start to drop around that time. What are the dates you guys will be out?