I'm not in the know personally. So which p2p softw are you using?

There's been discussions about blocking sites that spam since they fall within a range of ip addresses. But there's also been some concern over this b/c they use dynamic ip's not static ip's. So blocking ranges of ip's might help, but might also affect a lot of innocent people along the way.

If you're using Limewire then you can follow the image example below. Keyword filters can be added/removed anytime depending on type of searches - as long as you use the Apply button.