Sure.
First there are general information:
-
Gnutella for Users - Gnufu - you should know this by heart.
Then there's a copy of the (recently died) Gnutella specification wiki (I'm the one responsible for not taking a backup
- together with the LimeWire guys).
-
Gnutella Development Forum - File Repository summary - freeHg.org
- The files:
Gnutella Development Forum - File Repository: Manifest