The APN list will initially show blank. To add a new APN, go to the APN list, press the menu button, then New APN (some don't realize this!)

2Degrees

Name: 2degrees internet
APN: internet
Proxy:
Port:
Username:
Password:
Server:
MMSC:
MMS Proxy:
MMS Port:
MCC: 530
MNC: 24
Authentication Type:
APN Type: default 

Name: 2degrees MMS
APN: mms
Proxy:
Port:
Username:
Password:
Server:
MMSC: http://mms.2degreesmobile.net.nz:48090
MMS proxy: 118.148.001.118 (take care not to omit the leading zeros)
MMS port: 8080
MCC: 530
MNC: 24
Authentication Type:
APN type: mms 

Spark (it should need just this APN for both data and MMS)

APN Name: internet
APN: internet
Proxy: 
Port: 
Username: 
Password: 
Server: 
MMSC: http://lsmmsc.xtra.co.nz
MMS proxy: 210.55.11.73
MMS port: 80
MCC: 530
MNC: 05
Authentication Type : PAP
APN type: default, dun, supl, hipri, mms

Skinny

Name: Skinny Data
APN: wapaccess.co.nz
MMSC: http://mms.mmsaccess.co.nz/
MMS Proxy 210.55.11.73
Port: 80
MCC: 530
MNC: 05
Authentication type: 
APN Type: mms
APN Protocol: IPv4
User name and Password: 

Vodafone New Zealand

Name: VFNZ Web
APN: vodafone
Proxy: 
Port: 
Username: 
Password:
Server:
MMSC:
MMS Proxy:
MMS Port:
MMS Protocol: WAP 2.0
MCC: 530
MNC: 01
Authentication Type:
APN Type: default, supl

Name: MMS
APN: live.vodafone.com
Proxy: 
Port: 
Username: 
Password:
Server: 
MMSC: http://pxt.vodafone.net.nz/pxtsend
MMS Proxy: 172.30.38.3
MMS Port: 8080
MMS Protocol: WAP 2.0
MCC: 530
MNC: 01
Authentication Type:
APN Type: mms

Orcon

Name:
APN:
Proxy:
Port:
Username:
Password:
Server:
MMSC:
MMS Proxy:
MMS Port:
MCC: 530
MNC:
Authentication Type:
APN Type: default 

Name: Orcon MMS
APN: wap.orcon.net.nz
Proxy:
Port:
Username:
Password:
Server:
MMSC: orcon.nzmms.net.nz/pxtsend
MMS proxy: 172.30.38.3
MMS port: 8080
MCC:
MNC:
Authentication Type:
APN type: mms