How to Australian Actors/Artists get access to the USA for work... if they have no ''formal'' qualifications?

By getting an agent.

How this often works. An Australian visits the USA looking for work. He or she reads for parts and auditions.

If he or she is cast in a speaking role, he or she easily gets representation, which files all the necessary paperwork to get the work visa under which he or she will be acting.

So no, he or she doesn't get to just hang out for several years while waiting tables or stripping, hoping to get to be an actor someday. You either get in and make it or you go home at the end of the tourist visa.

Obviously, this process is easier for someone who has actual experience acting, rather than just says to themselves "I can do that" as those with actual experience might be able to get representation based on that former experience and proven work record.

The company which is producing the movie gets them a working visa, asking the government of the US to let them work in the States for a while.

Individuals with Extraordinary Ability or Achievement. PROVED ability, eg for World famous actors/directors etc

They first worked in Australian films and became well known there. Just Google Australian actors and read their bios.

They become renowned in their own countries first.

they would be at the top in aussie already ...in fact thy would need to be a househild name

and they get offered US contracts ...