There's two types of torrent trackers. Private, and Public.
Public trackers are sites like mininova and piratebay. You don't need to register there and there's no system of tracking upload/download. You download as much as you want and upload as much as you want. However, since this system is a bit flawed, in that most users download a lot and upload little, the speeds are very limited. Also, there is sometimes a lack of exclusive content like special editions of CDs and such.
Private trackers on the other hand reign in content as well as speed. Since you have to maintain a good upload ratio, a lot of users seed a torrent which results in a high speed download for you. Also, many of the private trackers focus on certain types of files and it results in a lot of content that remains exclusive to them.
Go get yourself an invite to a private tracker like torrentleech, or the best of all...oink.
I hope this is not advertising, but here's a small little guide. Hope you find it useful:
http://goobimama.blogspot.com/2007/0...oad-stuff.html