I can't find out if there is one. Have any Australians dropped out of high school but achieved their diploma some other way?

isnt the equivalent of GED the school certificate?

or at least in NSW it is

That's just NSW unfortunately.

if you mention where you are, someone _might_ have some chance at helping you....

not sure what you mean by GED.
but in NSW,

there's the school certificate, (year 10)
and higher school certificate (year 12), and the UAI which is part of the HSC.

if you dropped out, you can always go back to tafe, and do it at tafe.

in terms of diplomas, universitys have a 'mature aged entry', where you just need to convince them why they should let you get your diploma/do the course.

They're thinking of getting rid of the school certificate to force people to stay on for the HSC or drop out with nothing. Apparently this year is the last one, though they said that about my year too, so I don't know.