Moving your iTunes library to a new location
I realize this shit is posted in 1000 different places on the internets, but I wrote up some crap for friends anyway, figured I might as well post it anyway.
First, plug your old hard-drive and your new hard drive in at the same time. In iTunes open your settings, go to advanced, change the iTunes music location to the new hard drive.

Go to File -> Library -> Consolidate Library to move all your shit to the new hard-drive.

Everything will be preserved exactly as it was before.