Why not just use the unofficial Debian mirror on www.apt-get.org? I'm using this line in my Debian unstable desktop box's "/etc/apt/source.list" file:
#[MPlayer] deb http://marillat.free.fr/ unstable main
I guess its better to help the Debian project to get mplayer into the main project, but not everyone is a developer or wants to be. It works great for me and I'm guessing the codecs will not be Debian friendly anyway(so an unofficial source will be needed still).
- Dennis Dryden