not a hell of alot of places bud, only torrents or copy a live streaming video. even ebay u can find video discs or even as another way buy them from itunes but with itunes u have to use ur ipod.
I buy a lot of music DVDs on ebay and Amazon auctions. People buy them, watch them once and then put them up for sale used. I have a case with 50 or so concerts and music video collections (most of them burned from the originals that I keep in the house) that I keep in my car.