When you boot up backtrack, open up a terminal and type 'lspci'. You'll see a list of your PCI devices...in that list somewhere will be something along these lines:
05:00.0 Network controller: Atheros Communications Inc. AR5416 802.11abgn Wireless PCI Adapter (rev 01)
03:00.0 Network controller: Atheros Communications Inc. AR5418 802.11abgn Wireless PCI Express Adapter (rev 01)
One of those cards is straight out of my macbook pro, the same revision as yours, and both work superbly. If your readout matches either of those exactly, then you should be able to figure it out with the help of the google terms 'ath5k', 'ath9k' and/or 'madwifi'.
If it doesn't match exactly, well those terms will probably help anyway.
As an aside, I got some really nice results in OS X by porting kismet with fink/macports and then running kismet as a drone, which I then set kismac to listen to. The result was full functionality with an airport extreme from within OS X (no virtual machine), the robustness of kismet, and the graphical practicality of kismac. If you want to try that route, it wasn't entirely straightforward, you need to make sure to get the kismet-devel and not the kismet-newcore, and tweak a thing or two.