Unfortunately snooker matches are rarely, if ever put on torrent sites or the newsgroups. There is one private site that did cater for them extensively but last I heard the members moaned so much about everything(from which matches to higher quality, you name it) that the guy that was capping them gave up doing snooker. I don't know if he has relented though but it's nearly impossible to get an invite.
Edit: There is no snooker on the newsgroups going back 500+ days. There is some on some of the public torrent sites but if you going down that road be well firewalled and use a proxy.
Don't forget, you can also download Youtube footage, again though be careful. Some of the downloaders come with some nasty extras.