Decentralised might sound good, but each P (peer) in P2P networks which you connect to need, and can see, your IP address, unless there's a technology to counter that. I don't think proxies/VPNs can counter it.
Programmes such as PeerGuardian, to block certain lists of IP addresses, is useless, so I've read. Using Tor, while hardly safe with so much surveillance, isn't good for P2P networking, or at least not good for torrenting.