Ging

Hard Yakka do a long pants with knee pads. http://m.hardyakka.com.au/accessories/kneepads.html

Blossom79 is correct you will need to do a test here for heavy goods, there are different categories depending on what you need to drive, http://www.rta.nsw.gov.au/licensing/licence_classes.html, I did an HR in SA and it was basically a 12 hour day with a trainer, some theory and a lot of driving, with a driving test at the end of the day with the trainer also being the examiner.

Try this, http://www.repower.com.au/en/jobs/

Most big sites won't accept a white card done online now, you need one with a photo on it, as most people have said its a easy half day course. Also look at joining CITB as you will get a discount on training.

I think OTSR is issued when you have done your skills test in the country you are currently living and a ARTC is issued when you are resident in Australia allowing you to carry out any gap training.