Torrent trackers are sites where you can exchange links to files being distributed from users' computers. It can be anything: movies, games, music, programs. thenewpiratebay is, for me personally, the best one I've ever used. Here you can find everything. Tutorials, books, music, movies, TV shows, games, software, OS distributions, and much more. It's quite strictly moderated, so there's almost no "garbage". Each movie has a description, screenshots, and you can read the comments on the distribution.