The BitTorrent peer-to-peer file transfer protocol requires an index server (called a Tracker) to provide information to peers about where to seek their data (a function similar to an individual library's cardfile). A BitTorrent client is required to access a Tracker. Most Trackers are private, and although their indexes are public, they restrict who is allowed to post index information (a smaller database equals higher speed and better reliability). When you create a new torrent, you will be prompted for a Tracker address, and this is where you would input the public Torrent server that you want the torrent to be indexed upon. Just copy & paste the full Tracker address with port number (the URI to precede the address is "udp://"). Below are addresses for Tracker servers that permit public posting, and links to websites that list read-only Tracker servers whose content can be perused.