The port depends on the server -- usually it's 27910.
As for why the serverlist is not working:
a) Are you using build 13? (build number displayed in lower right)
b) try deleting serverlist.dat from the pball directory, then load the game back up.
c) check for any connection errors at the console (hit ~ to toggle it).
d) Try connecting to a server manually. Go to the server and type "connect 209.123.8.57:27980" (no quotes). If that doesn't work, there is something else wrong with your connection, or something blocking the connection.