iTunes music is eating my HD...how can I move it to another drive?

[SteveJobs]

If any of you have done this, I'd like to know the best way to do so.

How can I move my iTunes Music, which currently my wife and I share via the SHARED user folder, to another drive?

My options are:
1) attached firewire
2) server (I have an older Mac with GB ethernet acting as a server)

Can I move it to one of those? If so, what are the procedures? Pros and Cons, too?

tia