The relevant stuff from /etc/apt/sources.list:
deb http://ftp.us.debian.org/debian stable main contrib non-free
deb http://non-us.debian.org/debian-non-US stable/non-US main contrib non-free
#some things need oldstable
#deb http://ftp.us.debian.org/debian oldstable main contrib non-free
#some things need unstable
deb http://ftp.us.debian.org/debian unstable main contrib non-free
#For VLC media player
deb http://download.videolan.org/pub/videolan/debian sarge main
deb-src http://download.videolan.org/pub/videolan/debian sarge main