Create your own torrents

Here's how to do it for various torrent clients (but doesn't include Opera for some reason)

Edit: (23/12/2007) I.m having trouble with this. Making the torrent is very easy (some further methods -- including one from the command line -- shown here) but I can't figure out how to make the file available for upload. I'll post more when I figure this out.

Apparently, you need to submit your torrent to the tracker site. Here's some explanation on how to set up opentracker on your computer.
This appears to me to be very complicated at this stage. Here's another article dealing with how to create bit torrents from CDs.
I'm still not quite getting the hang of this but here's another useful detailed article.