Can I change my music location for itunes to external hard drive on my mac book pro? I have itunes setup with my music in the Music folder on my mac book pro.  I am now realizing that i am going to run out of space soon so i would like to change this to point to an external hard drive. 

First question is what is the best way of doing this?

Second question is does this cause a full resync or does it realize that i just moved from one place to another without a required wipe and download?
Apple has a support document for this, there isn't very much to add to it...