you can download music videos with torrents or p2p (if you're willing to download such software), otherwise i just randomly search google, or go to
www.ebaumsworld.comfor downloading/''borrowing without permission'' videos from certain sites, i'vebeen able to use the cached files to get the videos, if the format won't work, a cache converter program might (i don't remember any but i'm sure you'll be able to google for one). otherwise... i don't know
all in all... google's pretty useful