Go into the iTunes Preferences on the computer the music is on and in Sharing select "Share My Music." On the computer you are trying to listen to the music on, go into the iTunes prefs and in the Sharing tab select "Look for Shared Music"
Also note that you need to be on the same subnet. If your LAN is a large one, chances are there are multiple subnets; you won't be able to share with anyone not on the same subnet as you.
Comments
Go into the iTunes Preferences on the computer the music is on and in Sharing select "Share My Music." On the computer you are trying to listen to the music on, go into the iTunes prefs and in the Sharing tab select "Look for Shared Music"
Well, not without a little help anyway...