I'm not a Mac guy either, but seeing as the Mac guys aren't responding, I seem to remember that on the Mac there is a /var directory that I think stores the Subsonic information. Again, it's just a guess on my part remembering other posts I've read. You should be able to search and find the instructions you need as I'm almost certain they have been discussed previously.
Edit:
http://forum.subsonic.org/forum/viewtop ... +directory
Please notice:
o Installs Subsonic application in /Applications/Subsonic.app
o Installs other files in /Library/Application Support/Subsonic/
o Uses port 4040 by default.
o To change port number or other basic settings, edit /Applications/Subsonic.app/Contents/Info.plist
o For trouble-shooting, start /Applications/Subsonic.app/Contents/MacOS/JavaApplicationStub in a terminal and look at logging.
This is from the Tutorial section at the link above. HTH