I've been in Darwin for about 2 years now, and only got my first job after 12 months.
The ONLY way you will get a job is
1. Be prepared. RESEARCH!!!!!
2. Be willing. That said, don't pay for work and don't work for free, it just insults your self and everyone else that has paid up for their commercial licence.
3. Be there (this is a big one.... Don't ring if your not going to turn up, don't send a letter if your not going to turn up. If you don't turn up, you WON'T get the job)
4. Don't give up. I have met HEAPS of unemployed pilots that have stayed through the hard times and made it. And I have met HEAPS more that gave up after a month then went home. The guys that stayed have jobs in planes, the ones that don't have jobs at Maccas.
If you turn up to a company enough, they will eventually know your face. You will get to meet the other pilots you might be working with and, if you get on with them, they might just help you out a little. You won't get a job by just driving around the GA apron looking at planes, you have to go INTO the building and talk to somebody.
As far as the Instrument rating/Instructors rating is concerned. If you have the money, it is a good investement. It will give you more hours in the log book, and more confidence in your abilities in the aircraft. Getting "heavy" single time in your logbook isn't always the best way of spending the few $$$ you have left. They cost alot to hire per hour, so unless you've got it full of friends on the way to the beach or Birdsville, you won't get your money worth. All of the operators WILL give you ICUS once you start. It's not like they just send you out with the keys and MR to a community and say "good luck". Its not in their interest. Just get the extra hours in the log book and the extra qualification for the resume. Someone before said that alot of operators look down on instructors and instructor ratings... that might be true, but others prefer instructor time for exactly the same reasons.
Good luck all, take the plunge and get your self up into the heat.