I discovered a neat resource the other day which is available to anyone who has a library card through the SDC library system. There is a collection of online databases that you can access simply by putting in your password which is on the back of your library card. Most of the databases are not specific to New Zealand but they do have the Australia/New Zealand Reference Centre which is great for accessing newspapers and magazines.
You can find the links to the databases here: http://www.southlanddc.govt.nz/services/libraries/online-databases.cfm
Just click on a database, sign in, and put in the keywords that you are looking for. It's great that we have this resource for free. Thanks SDC.