It depends on what city you are departing from. However Qantas, V Australia, Delta and United all offer direct services from Australia to the US (namely Los Angeles). Qantas also flies to San Francisco and New York and Delta onto Atlanta.
However, Air New Zealand, Air Pacific, Air Tahiti Nui and Hawaiian Airlines all offer services between Australia and the US, however they are not direct.
west
Northeast
Southwest
You are more or likely to go west.
Australia
west
You can go either through New Zealand OR fly to Nadi and go form there. If you are already in Western Samoa, Apia you can fly out from there.
The quickest and most direct route from Australia to South Africa would be to go west.
If you are going against the wing/gravity you will not go as fast and it will be more of a struggle to fly.
If you flew across Australia from LaGrange to Sydney, in what direction would you be traveling?
Go Fly a Kit - 1957 was released on: USA: 23 February 1957
As Australia is an island, people have to either fly to Australia or travel by boat. Almost entirely, you travel to Australia by air. Only cruise ships and freight go by sea these days.