As has been stated, you need to supply some more information and do a bunch of primary research in the various message threads here.

That said, here's something to get you started. You can save about US$1,000 by originating in Canada rather than the US. The 4 continent coach fare from Canada is around US$2,658 while the same trip originating from LAX is US$3,700. These figures are based on current exchange rates and exclude taxes, airport fees, etc.