Just make sure that your iTunes folder (on the Mac that actually contains all of your media) is shared, or share the volume (hard drive), itself. Your specific settings might vary depending on the location of your iTunes folder, your admin settings, etc., but if you can access the iTunes folder from your other Macs, you're good.
If you'd like, replace the default iTunes folder in your User -> Music folder with an alias to the iTunes folder on the remote Mac, (the one with the files).
I've got my iTunes folder on my server in the root level of a secondary hard drive with File Sharing turned on, so I just log in on my other Macs as an admin and I have access to the volumes on the server.
On the Mac that you'd like to connect WITH, mount the hard drive or iTunes folder with all the music. Open iTunes and go to Preferences. In the advanced tab you can change the default location for your iTunes Music folder. Select "Change," navigate to the shared iTunes Music folder and select it. If you have to, quit and restart iTunes. iTunes should now load up all of your media from your remote computer.
That's it.
You can also edit or add music, as you'll be editing or adding music directly to the Mac that's serving up your media.
Alternatively, you could try Home Sharing, but I'm not sure if you can edit or add media remotely or if that works with Front Row.
One side note: I've got this set up with 3 Macs. One Mac is the server and I rarely launch iTunes on this machine. I use 2 other Macs to access the library, though. Previously, when I would open iTunes on one Mac, quit it, and open it on the other Mac, iTunes would go through a lengthy "determining gapless playback" procedure on launch. When I would quit iTunes on this Mac and open it on the other Mac again, it would do this again. To remedy this, I just selected all of my music and under the setting for "Gapless Album" I selected "No." iTunes no longer does this procedure when I alternate Macs.