Rarely will a torrent work with iTunes. Some of the best software for only reading and accepting legitimate files (bad news for all my downloaded movies). Seems much more strict for movies than songs.
In terms of searches, I used thepiratebay.org for over a year but isohunt.com encompasses even those searches. As said, I've literally never come up short in a search.
In one day, I had the entire series of The Wire, The Sopranos, Deadwood, Rome, The Office, & Six Feet Under all at the very least queued up. In less than 5 days, I had them all.
Great success!