You can access your domain email by using programs that support POP3 or IMAP, including mobile phones. You can also access email via your website by going to www.yourdomain.co.nz/webmail in your web browser (or mail.yourdomain.co.nz if you are on the windows server).
You have a choice of several webmail programs (on the Linux hosting plans) to use at HostingNZ:
You can also use an email host like Yahoo or Hotmail to retrieve your domain emails, without having to log into your domain email service.
If you use a third party mail program to get your mail (like Outlook), it may pay to configure the program to not leave the email on your host account, which will help preserve some disk space.