One other thing you may want to check out:
Soulseek.
Soulseek is another P2P program that allows you to do more of the same that KaZaA and friends do, but I find the organizational and community bonuses very worthwhile.
For one, you're able to browse other users files
very easily. While browsing, if you want to download an album, all you need to do is right-click on a folder and download it. The music hits your transfer list and at the end of the day the folder and it's contained files are on your hard drive, making downloading albums and sets of items a breeze to do and a breeze to catalog.
The buddy list features are sweet as well, allowing you to reward users who share with you and ban those who try to leech.
The community of people using soulseek spans the entire world, and there are serious, serious music geeks on there to cater to even the most whimsical music tastes. On a good day I can find Noam Chomsky AudioBooks, Entire Seasons of Saved By the Bell, and 50's Doo Wop that never made it past an LP - and all of it at a decent speed and with little or no fuss.
As a footnote, the program began based on an IDM and Downtempo techno newslist, and a large chunk of the user base of soulseek is for Techno lovers. If you're into the beats, don't sleep on Soulseek.
http://www.slsknet.org/