This resource is at the Auckland University Library and is a wonderful effort mainly from the Australian National Library but with input from a few New Zealanders. This organisation seeks to preserve historical Pacific content from degredation in tropical climates in the South Pacific and comes largely from private collections. Well done.
It can be a bit intimidating to visit a university library if you are not used to it, crowds of students and no parking places but it is worth the effort. To find the Special Collections Library, go in the main doors of the Library and head towards the stairs then veer left before stepping up.
The index of what is available is in blue folders if you haven't already identified which microfilms have your area of interest on them by accessing the online catalogue.
I did a search on Niue, there were 39 results.
Another search on New Bedford ( USA + Pacific whaling ) brought back 25 results, most of which are very interesting.
I can see myself spending some time at the microfilm machine soon.