Four Seven Eleven
Question 2
Under the FAA system VFR aircraft in class g or E airspace are not required to be using any particular radio frequency.
They do however have the option of maintaining "VFR Flight Following" from whoever the nearest ARTCC (Center) frequency happens to be. This is due to the widespread coverage of radar in the USA.
The NACO publishes a booklet called the Airport/Facilities Directory and it is updated every 56 days. It will tell you what the frequency to contact is in your area.
What is the coverage of Class E airspace down there? In the USA most of the country is class E from 18000 down to 1200 agl and in some places 700 agl or even down to the surface.
There is not too much class G left except in remote parts of the country like the Western Mountain ranges.
And as for Mode-S. It is set to become compulsory in the USA also. It is already deployed in some major cities. Great system.
Do they have Class B in AUstralia?