The Device SDK is only available on NDA basis. I know a person who
managed to develop a plugin for the Apple Newton (!) under iTunes 2 for
MacOS9, but he had a "friend on the iTunes team".. Nothing has come out
for OSX, so either he hasn't had time, or Apple doesn't want it done.
I've heard that Apple is quite 'picky' (right word?) about who they allow
access to the Device API..