Hyriand got tired of making patches for Pysoulseek, which apparently isn't going any further, and took over the whole shebang. Nicotine is the result, and it works a treat. There are some installation instructions for OS X over here. Still can't get GeoIP to install yet though, to block those sneaky Americans ;)
Update - GeoIP works. Read the full post for installation notes, assuming Fink's already installed.
Download the GeoIP C API.
Open Terminal in the downloaded folder, and run:./configure --prefix=/sw
make
make check
sudo make install
Download the GeoIP Python API.
Copy geoip.h from /sw/bin/include into the downloaded folder.
Open Terminal in the downloaded folder, and run:python setup.py build
sudo python setup.py install