For those of you who are interested, I have created a web-based tracker going off of the PHP code that was suggested earlier in the thread.
I modified it a bit, and it seems to work fine. I uploaded a copy of it to my server for all to use. I'd appreciate comments/concerns/feedback. Also, I'd appreciate it if you limit searches to 2-3 ZIP codes at a time and just overall being not so obsessive when refreshing. It does take a while to load because it is pulling all the data through the Target servers for each model (18 if my math is correct) and each zip code you enter.
http://nicroth.com/ipad/
Enjoy.
PS: If my server blows up, well, I'm sorry. I tried!
Update: I modified it a bit more. Now you can select which model(s) you wish to check each time.
Best of luck finding an iPad 2!