The Drivers for the Alfa AWUS036H , From OSX 10.4 to 10.6 are the same. You can find all drivers, including Windows, from XP to Win 7, Linux and all Mac OSX at this location http://kismaxx.blogspot.com/2010/10/free-wifi-app-software-mac-windows.html
Tried downloading that driver archive, and I only see the 10.5 Mac driver (which one user reported crashed his 10.6 Mac). The Alfa site is "down for maintenance" which could mean anything. Does anyone have the 10.6 driver? I would appreciate it if someone could email it. Reply if you can help. Thanks!