how bout some mechanical engineering trade
im a mechanical fitter and turner and i find this to be the best trade, some times the job can get kinda dirty but if i was 17 again id do it again, i finished my time in 3 1/2 years and came out with my cert, $4000 in tools paid for by my work, and great skills which led me to my current employer, im currently 22 and clear between 1g and 1.5g a week.
the best bit about being a fitter is that not only are you working with mechanics, but your tools (spanners, sockets, torque wrenches, etc) are paid for (pipe wrench no good for a car) the extra savings like getting trade price at suppliers by saying you work at ???????, and also the boss doesnt mind if you bring in a turbo or starter motor to reco during work time using work parts, cos its considered "training"
choose maintenance fitting!!! thats what i do and i love it, at our work we machine, weld, fabricate, repair, modify, and of course foreigners.
i much prefer this than working at a jobbing shop doing production work.
but one important thing to keep in mind, choose big businesses:
lots of tradesmen= lots of work,
check out their steel rack= not afraid of spending money,
ask where the company is going in the future= assess how far off china taking over is- its a sad reality but you have to be prepared for it.
tafe= most big business will pay for it and other courses needed as well
but do a day or a week work experience and find out which you prefer