I've found few interesting websites that will help you to find a job in New Zealand:
Seek: http://seek.co.nz
Immigrate to New Zealand with a job: http://www.newjobz.co.nz/static/welcome.html
Netcheck: http://www.netcheck.co.nz/
Job offer: http://www.joboffer.net.nz/
Hope it helps!
If you know other websites, please post their address in this topic