I thought I would add my experiences with QF into the mix. I did a Mechanical apprenticeship starting in 96 and finishing in 00. Bear in mind that much may have changed since then.
Don't get too worried if you receive papers from QF where the application date has already past. This is just how things work there. Fill in the forms and send them off. Do tick the AME box, as it is generally easier to get onto better things than ticking the AM box.
The initial testing for the apprenticeship consist of a set of aptitude tests. From memory, there is a mechanical aptitude test (i.e. you are given a drawing of a gear train and you must figure out which way the various gears turn / drawings of various shapes and you must decide which two items are identical etc), a English grammar test, a mental arithmetic test, and one more that escapes my memory (may be a short written test on your motivations for working with QF / why you would be a good engineer etc.)
The interview is the next stage if you pass. This used to be conducted by engineering personel, so there was none of the usual nonsence you get with job interviews. If you were going for avionics, you are given a circuit board where you have to identify various components. Mechanical guys are asked to describe the workings of 2 and 4 stroke engines with the aid of a sectioned engine.
If you get the apprenticeship, you then start your training. This used to be a combination of the first nine months at the QF apprentice training school (don't think it exists anymore). You go to your fist section in the last three months of the first year. Second and third years alternates between rotations at the jetbase, and block release at TAFE. Fourth year consists of rotations at the jetbase.
You can get a degree through QF (cadetship), but you will have to finish your apprenticeship first. Bear in mind, that the cadetship is another eight year commitment. You spent the fist two years at uni, and the alternate between a year at QF, and a year of uni. At the end of this, you have to give another two years to QF. You can apply for Mechanical and Aero engineering, and another degree, which is basically a management / business type degree. Bear in mind that the final choice as to the degree you get is decided by QF.
On a personal note, if you want a aircraft maintenance engineering trade, with experience on the big jets, then go for QANTAS, as it is the only employer offering this in OZ. If you do like planes, it is very interesting, but bear in mind that there is lots of tedious crap as well.
Also bear in mind what the old hands have said. Training was always a contentious issue at QF. It is certaily a case of "it's not what you know, it's who you know". Also be prepared for shift work and the restriction it places on your life. It certainly gave me the ****s when my mates were out and about and I was working.
The best way to possibly see it, is gaining an apprenticeship and some experience that you use to get into other areas. Of the 5 blokes that started with me as mechanical AME's, 5 have gone back to uni (3 thru QF cadetship, 2 including me off our own backs) with only one left still at QF.
My colleagues still at QF genrally reflect the sentiments of some of the older hands who have written here. That is, things are not what they used to be, and going down hill.
In summary, go for the apprenticeship if you want to, as not many people ever get to play with jet engines and 747's, but keep an eye out for other opportunities as other have said. Think of your QF apprenticehip as a stepping stone to stuff outside of QF.
Regards, JetMech