If you're after music try Soulseek. Although it sounds like some dodgy dating service its actually a superb, adware/malware free, P-P client. Although you do have to sometimes "ask" permission to download from some users. I've found everything on there from the deepest minimal grime-glitchism to Haddaway.
Check it here: http://www.slsknet.org/
Avoid Limewire/Kazaa/Bearshare, etc. like the plague, unless you want your browsing habits to be monitored by a purple monkey that wont go away even after hitting ur machine with a hammer.
I also agree Torrents are gud (better for films, software, games (limited to only popular music imo)): Try (client):
uTorrent - http://www.utorrent.com/
Azureus - http://azureus.sourceforge.net/
and grab yourr torrents from http://www.mininova.org/
Furthermore, you dont actually have to pay to access USENET. USENET has been around since the single-cell organisms roamed the earth and I believe it was created by a sentient race of limestone oblong shaped blocks. USENET has no reliance on other peers e.g. for torrents or P-P so you get MAXimum speed for your connection downloads.
Your ISP "should" provide a USENET server for you to access. For NTL the server address is "news.ntlworld.com" on port 119. You will need a usenet client to access, and one capable of rebuilding those usenet posts (USENET is actually a BBS) into full length hollywood bollux is Grabit: "http://www.shemes.com/"
As mentioned in this thread however, you may get a richer selection of goodies if you pay to access a USENET server (e.g. using the USENETX client). Grabit also offers this "pay" service, but its worth using the torrent method if you cannot find what you want on USENET and spend those pennies saved on custard creams.