I use 'Napigator' from
www.napigator.com
It enables Napster to use alternative, non-Napster controlled servers.
There's any number of them available since it's an open standard. Many of them have more available files than Napster's own servers. The one I'm connected to at the moment has over 105,000 files / 6,200 Gb available.
The only catch is that it often takes me a number of attempts to find a server that's not declining connections due to capacity constraints. This started after Napster's legal woes.