flights to S. pacific from aus/nz

I couldn't get a flight to a South Pacific Island as part of the particular rtw ticket i have but am hoping to get a cheap flight from either Aus or N.Z. when I get there. I will be looking to fly from Aus around 18th Dec or the week following , or alternatively to fly from Christchurch the same week or from Auckland around 10th January or the following week.
I am currently in Nepal and am finding it hard to access info re flights. Could anybody recommend any airlines offering cheap deals to any S. Pacific destination and rough prices? I would prefer Samoa or Cook Islands but will take what I can get!
Many thanks for any advice.
Cheers
Fishtails

Both Virgin Blue and Air New Zealand fly to both countries.

Check their websites to see which one offers the better fares - Samoa is likely to be cheaper in any case.

Or try Air Pacific, if you fancy the idea of a Fijian stopover on the way to Samoa.

Flights from Aust and NZ to the Cooks are usually full way in advance for the period from about Dec 15 to Jan 1, as CI'ers living overseas come back home for a visit. Then they are full from about Jan 1 to 15 or so in the return direction. So, you might have more luck for the Cooks if you leave NZ in mid-Jan or so, than before Jan 1.

It was announced today that Virgins Pacific Blue will shortly start flights to Solomon Islands under a wet lease agreement with Solomon Airlines. That would be a good alternative and details should become available on Pacific Blue's web site shortly. Although the same applies to Solomons as Cook Is. every-one living o/s flies home for Xmas and then back out early new year. Also Ramsi personnel fill the flights in the reverse, out for Xmas back in the new year.