Thats way expensive!
For us flying from Sydney to LAX... on air NZ Peak costs us $1600 (thats US $ 900)
And at the moment theres a special to fly there for $999 - about US$ 550
(if course this wouldnt include Cairns, so you'd have to buy this separately...)
Then buy a Syd-Cairns fare - about $400-600 aussie (US$200-300)
but have a shop around and also check out discounter travel agencies... like STA travel - i know there's one in LA that i saw while staying there-
In Santa Monica... on SantaMonica Blvd and 4th.
Hope this helps
Anything else oyu need- just email me....
Malcolm (in sydney)
p.s. whatever you do dont fly United 744's long haul - rather stick to Air NZ