Here there are some links to information about Go Servers

How to Play Go on the Internet [Mindy McAdams]

What is an Internet Go Server? [Ken Warkentyne]

To play Go on the Internet you have to telnet to one of these server

IGS	(igs.nuri.net port 6969).
IGS	(igs.nuri.net port 7777).
NNGS - No Name Go Server	(nngs.cosmic.org port 9696).
LGS - Legend Go Server	(lgs.hinet.net 9696).
WING - Worldwide Internet Gokaisho	(wing.brlnet.net 1515).
HGS - Hermony Go Server	(weiqi.online.sh.cn 8888).
CWS - China Weiqi Server	(cws.weiqi.net 9696).
FGS - Fukui Fuzzy Go Server	(fgs.fuis.fukui-u.ac.jp 9696).
goclub.org Go Server	(nngs.goclub.org 9696).