[Macpartners] keep music on external hard drive

[arthur steinberg]

i am using a g4 powerbook running os x.4.10.  i have a la cie external 
drive that i back-up onto, using chronosync. i am down loading more and 
more music onto my laptop's harddrive and would like to keep it on the 
external drive instead of on my laptop.  how do i get itunes to 
recognize that my music library is on the external drive rather than on 
the laptop's hard drive?

thanks for your help.

arthur