hi cybie,
Try the tafe website
http://www.tafe.sa.gov.au/default.aspFrom here you will be able to find vocational courses at the different institutes around SA.
If you do find a course just make sure that it is an "approved course", I think Tafe has a list, I think all this means is that it has a CRICOS code.
Once you find the course then you'll apply for the course, get an offer for a place, accept it by paying 6 months up front and then have medicals and apply for the student visa. You can only apply for the visa six weeks before the course starts.
The student visa section of the immigration website should have all of the info you need. You definately have to study for at least two years, to be exempt from work experience, but the TRA or whoever assesses the qualification may require some form of work experience, you will need to find that out yourself.
Good Luck,
Tracey