Try Companies like Extraman, Skilled, Mondelphos, Barminco, Ausdrill. Best to have your HR licence and get a police clearance from the GSDU for work in gold mines, Just be persistent and it will happen. Try the oil rigs also plenty of work there companies like Offshore Marine Services (OMS), Total Marine Services (TMS), Global Resource (GRN). If you are not a tradesman you will need at least a dogging ticket preferably a riggers and a HUET (helicopter underwater escape) is a must. Having been in the mining and offshore game for many years the best advice is to be persistent and polite with the HR girls, they get hundreds of calls a day from job seekers. Send off your resume and call them within the next few days just to ask if they have received your Resume, Get there name and BE polite just so you have a contact for when you call back to touch base.
Best of luck