Torrentz.com is a great site. It is a basically a one stop destination for any torrent search. I personally find it very useful as it automatically syndicate all the torrents from various sites like piratebay, mininova, demonoid etc.
Before downloading any movie from torrent I usually check its rating, synopsis & star cast on IMDB. I find this process very cumbersome and boring to search each movie on IMDB. To ease out this process I searched for a GM Script(GreaseMonkey Script).