I used this tutorial with great success:
http://dhruvgairola.blogspot.com/2012/10/raspberry-pi-with-neogeo.html
Please note that for my installation, installing ZLIB was NOT OPTIONAL. W/R/T the BIOS files, they need to be unzipped inside /usr/local/share/gngeo You will need all of the following BIOS files:
gneogeo.zip
neogeo_old.zip
neogeo.zip
uni-bios.zip
After you get everything in place, you may also need to modify how the es_systems.cfg executes the emulator. It helps to manually run the command from the command line instead of through EmulationStation in order to debug.