Copy the trackers.
Doubleclick the torrent you're downloading in your download client (uTorrent etc).
The torrent info box should appear with the existing trackers listed.
Paste your new list at the end of the existing one, remember to leave a
blank space between each tracker.
Here's a brief youtube vid which shows the above: http://www.youtube.com/watch?v=ndbJ8umX_yU
NOTE: This thread is a few months old and some of the listed trackers are now faulty.
After you've added them click 'Trackers' in your download client and check which ones are
not working (timed out etc). Right click on the faulty tracker and select remove.