2 Ubuntu Music Machines

I've converted an old clunker HP Pentium III computer into my juke box hooked up to my home entertainment center. I put Ubuntu 7.10 and Amarok on it, and it's working great despite what an old machine that is. My original plan was to make that my only use of Linux. However, when I saw how terrific an OS Ubuntu is, I decided to expand my use of it. I ordered off for a debranded “No OS” HP, an Athlon 64 3800 with a gig of RAM and a 250 gig hard drive. I don’t have it yet, but will soon, probably tomorrow or the next day. The plan, for starters, is to put Ubuntu 8.04 and Amarok on it and network it to the Pentium III box via a simple wired network. That way I can edit my music collection on the better performing machine, which is also in my office and is hence more comfortable than the living room. So what I’ll want to do is copy via the network the music collection, the Amarok database and config files from the Pentium III to the Athlon 6400. Then I’ll do my editing and copy it back. (The result will also be a backup of my music collection.) I’m hoping there’s some Linux-based software that will let me do this easily. If I were doing this in Windows, I would use Second Copy (http://www.centered.com/). That program lets you set up profiles that always copy specific files to a location that you designate. I want to be able to create two profiles, one that all the necessary files from the Pentium III to the Athlon 64, and another that does the opposite. Obviously, I'll need the copying to be simple copying and not conversion into some kind of backup format. What program would you suggest for this? Also, should I upgrade the Pentium III's OS to Ubuntu 8.04?

is the machine in the office always on? because it might make more sense to keep the music on the office machine and put in in a network share, with something like Samba then play it over your network. Doing this will also allow you to play it on any other machine in the house, with either windows or linux...