If you've decided to use the shared folder approach, you'll be happy to know that accessing shared media in iTunes is easy because iTunes is happy to load its files from any location. Follow these steps:
On the Mac that will hold the shared iTunes Music folder, in the account for the
user who will be in charge of the folder, open the
From inside that folder, select the iTunes Music folder.
Choose File > Get Info.
In the General section, check Shared Folder. (If Leopard pops up an alert telling you to enable File Sharing, click Enable.)
If you're using that user account to log in over AFP from other computers on the network, you can skip these next steps; otherwise, set up a user and permissions for ...