Ten Yard Torrents is better for nfl and ncaa games. (you need to login to get the torrents, organized by week).
i use azureus for torrents (
SourceForge.net: Azureus )
and for demonoid.com, you have to give out invitations 1 by 1, and if the person you invite gets warned or banned, it can come back and get you banned too (for leeching etc).