Depending on what you want to share, you can choose between these trackers, which in my opinion are the best:

IPTorrent - General
Torrentleech - General
Cartoonchaos - TV toons and kids
TVvault - tv retro
Secret-cinema - movies retro and rare
Tvchaosuk - tv uk
Blutopia - HD
Bibliotik - books
Gazelle Games - games
Redacted - music
BroadcastTheNet - tv
PassThePopcorn - movies
Karagarga - classic movies and rare


Those are the best private trackers according to my opinion.
The most accessible trackers for newbies, as they are MAM, RARG (TRACKER free), rutracker (tracker free russian).
In the open records section of this same forum you can get some tracker.

http://torrentinvites.org/f37/