The folks at irc://freenode/gtk-gnutella helped me solve a problem where I was not getting any search results. I'll post the solution here because this forum seems to be a cental location for troubleshooting.

The problem was that I was not getting any search results, no matter what I searched for.

I started gtk-gnutella from a command prompt, turned on Search debugging, and found that every time I executed a search, a message went to the console saying something to the effect of «Discarding invalid empty search ""».

The problem was that I configured for extended nonlatin character support, or ICU. I reconfigured and recompiled, and the problem was fixed.

When you run Configure, remove "-licuuc" from the propt that asks which libraries you want to link to.

My version of the ICU library is 2.6-94, and it is yet unknown if this was a specific bug with that version of the library.

Any comments or clarifications by people who know this program better than I do are welcome.

Sometimes it helps to watch what clients you are connected to.
Set your connections to more than 10, wait till you are connected to valid nodes like limewire or bearshare and then do your search.
After you get your results, set the number of connections back to normal.