Kazaa Lite was being developed by a group who wanted to remove the spyware, adware and extra garbage that came with Kazaa, they used the name Kazaa but it wasn't an official product. In December they got shut down and there are no new releases of the program being offered. As for what is transferring over it's network, I've always found Kazaa to be quite unreliable but pretty much the only alternative worth using.
BitTorrent is not a pay program, you just need to know the good sites in order to get what you're looking for. Most of the good ones have become private in order to reduce leachers and limit legal backlash. Personally I still use suprnova.org and torrent-addiction.com (aka digital-update).
If I need a song that bad, I'll look for it on Kazaa, but usually I just look for albums I like on
www.suprnova.org or torrent-addiction (member site)