Your main source of information will be the website of the Consulate General of Ireland (external link) in Auckland.
For further details please contact:
Consulate General of Ireland
Level 3 Tower One
205 Queen Street
Public counter hours are from 10am-1pm and 2pm-4pm
Phone: 00 64 9 9772252
Fax: 00 64 9 9772256
Website: www.ireland.co.nz (external link)
Web page for Working holidays: www.ireland.co.nz/working-holidays/ (external link)
The Irish Naturalisation and Immigration Service (external link) also provides information on visas for Ireland.