You have an interesting trip planned but keep in mind that if you travel during southern winter then you'll be hopping between freezing temps and tropical heat. Australia and NZ can get pretty cold in winter but Pacific Iles are pretty warm. The best place to shop for vacation packages would be Australian weekend papers like Sun-Herald and Sunday Telegraph. Packages for Fiji are about US$300 for a 5 night stay including airfares from SYD with Vanuatu being just a bit more expensive. French Polynesia would be about US$550 for a package deal.