Hi,
It's abit hard to help you, since you arn't specific in your question.
What is it that you need, and for what purpose?
Here are a few pointers:
1. If your looking for papers, I'd goto acm.org and search for P2P or peer to peer.
2. Take a look at
http://www-130.ibm.com/developerworks/java/,
javaworld.com,
onjava.com for tutorials/articles.
3. Search the net with google, msn, yahoo or something similar for java p2p tutorials.
4. Search the Javaranch forum: "Distributed Java".
/Svend