[Arizona (Steve)]

Karls48, I hope you won't mind if a guy from the U.S. jumps in here.

I pulled up a list of FM broadcasters in the Sydney area, and the band looks pretty congested. I doubt that you'll have much luck with the FM band at your location. Here in Arizona, there are dozens of micro-power transmitters eating up the whole FM band.... a lot of them are tucked in valleys and I don't normally receive them, but I seem to get a lot of reflections off aircraft.

You might have better luck on SW. A few years ago I tried a program called R_Meteor, monitoring the government WWV transmitter (15 MHz) located about 1000 km away. I imagine you could use Spectrum Lab the same way. Using SSB mode, you should see the carrier continuously. Meteors will appear as "spots" roughly 10 Hz away from the carrier, they fade away within a minute or so. The 10-Hz Doppler separation from the carrier is caused by the ion trails being carried along by high-speed winds in the upper atmosphere.
You can also expect to see aircraft tracks - these typically last two or three minutes (or longer) and they typically cross right over the carrier.

Here's a shot from R_Meteor. The horizontal bright band is the carrier, and it is flanked by a couple of sidebands (possibly artifacts from my receiver). Time scale runs across the top.
At 1659 you can see a little blip near the carrier - this is a typical meteor reflection.
All the other junk appears to be aircraft.