GnutellaPapers

[1] (http://www.andrewlaycock.com/thesis/download.html) - A Paper on Filesharing, Music and the Industry, for which a survey was done with p2p-Users.
[2] (http://www.pam2004.org/programme.html) - The 5th anuual Passive & Active Measurement Workshop

Also you can find some papers at the wiki page of the free Gnutella client Phex (http://en.wikipedia.org/wiki/Phex#See_also).

You can find more Papers using your favourite Search-Engine.