NZWired currently has an IRC server at irc.nzwired.net. The official NZWired channel is #nzwired. The channel is usually fairly quiet, but if you say something, people will usually appear fairly quickly.
To connect you'll need a client such as mIRC for Windows, xchat, BitchX?, ircii or EPIC for *NIX, and Ircle, Snak or Colloquy for Mac OS X (Ircle and Snak run on OS 9). Refer to the client's documentation for how to connect.
The network is currently maintained and run by PhillipHutchings. If you have the knowledge to run a server, I will consider linking. You'll need to run UnrealIRCd? 3.2 - http://www.unrealircd.com/
Nickname and Channel registration services are provided through Nickserv and Chanserv, and offline messaging through memoserv. sitharus is the network admin, and will answer any reasonable question.