Skypeing a landline in New Zealand

You can use either Skype or SIP (from companies such as Blueface).

You can use your PC or dedicated hardware ...... be aware that Skype phones are not compatible with SIP. There is hardware for either that will allow you to use ordinary phones - if you have one to spare.

You need to purchase "Skype Out" or a Pre-pay account for SIP to cover the cost of calls.
If this is a very regular occurrence then you may wish to set up a 'plan' where you get other benefits from the provider.

The charges for such landline calls are usually around a couple of cents per minute with minor differences between providers.

If the person in NZ also has a Skype or SIP setup, then you can call and speak to them without any cost, from a similar setup here.

If you use SIP (say from Blueface.ie) then you get a non-geographical number with your account which is accessible from all phones such as landlines/mobiles etc.

A reasonable/good broadband connection is required for best results.

I suggest you read lots of threads in this section to get an idea what people think of the various providers of such services.

Either method should give you very cheap calls to NZ and other locations around the globe.

regards.