vixen,
Yah-E is correct as usual! Arizona is on the new AADSAS form (available May 15), but the ADA has not updated the DAT registration packet.
I spoke with the ADA, and since I'm already registered for the exam, they asked me to simply fill out a score report request form with Arizona written in. The fee is only $10, which is the normal score report fee (beyond the 5 free included schools).
Since you haven't mailed in your forms yet, I would do as Yah-E suggested and give them a call. Perhaps they will just let you write your Arizona selection in on the school request section, rather than fill out a score request after mailing in your test application. Let us know what you find out!