If your using a Mac (kudos if you are!) then open the external HD icon that you see and click on the iTunes music file. Then just drag and drop that file into the music folder in the Finder.
In Windows I don't know the exact way but I think that you could just find the empty iTunes folder and drag your music over to it.
iMac G4 Aluminum iMac iBook Clamshell iPod 3G
iPod classic 1G iPod nano 2G iPod touch 2G iPod mini