Hey, I'm considering picking up a notebook with Amarok preinstalled (Asus eeePC).

Right now I only have one PC (OS X 10.4) with an external hard drive with all my music.

Since this particular notebook only has 4 gigs of space, I want to be able to stream my collection over a wireless connection.

Is this possible, and if so how would I go about doing it? Sorry if this is an obvious question

Amarok can stream music from shared Itune libraries.
Just import all your music from your external hd in Itunes on your Mac and in Itune preferences, choose to share it, then Amarok should see it. I think you will also need Avahi (Bonjour) client package installed.