Can i store unused iTunes Library on an external Hard-drive?

Hi There,

I have 3 account on my Macbook each have an itunes library on them, the on is use all the time, but the other 2 never change and are never listed to becausethe only used of the laptop!

is there any way I can move the library on to my hard-drive so i can free up space on my laptop, but still have accesses to them if i need to update the 2 of them to put new music on there iphone and ipods?

Thanks and help would be greatly appreciated??

Tom Green