Hello!

Preface: First of all, let me assure you that I never intended to speed on purpose - in fact I always tried to go with the flow of the other cars on the road (probably not the best idea in retrospective) and usually felt like one of the slower drivers because I was overtaken pretty often. I have learnt from the incidents and it will be my highest priority to drive below the speed limit at all times in the future.

Here's the story: I'm a visitor in Australia and will stay here for a few months. I arrived here in early September and bought a used car registered in NSW a few days later.
I didn't really realize that there are such strict speed limits (and heavy fines) here until about 1 week ago when I got my first speeding ticket in the mail. Another one followed a few days later. Both occured in NSW and have a fine of $243 each.
I recently drove from NSW up to Cairns (QLD) so there might be more tickets coming in the next few days/weeks (by the way, is there a way to find out about tickets that might be on the way?).
On my way up, I once got another speeding ticket on the spot from the highway patrol (or whatever they are called here). It was $150 but they told me that I do not really have to pay it because I'm a foreigner (Austrian citizen) and nobody will track me down after I've left the country.
So, basically my question is: Can I get away with not paying the speeding fines I received in the mail? I heard somewhere that tickets belong to a specific car rather than a person, so if the car is sold, the new buyer can get in trouble if the previous owner has not paid all fines. Is this true? I don't want the next owner of my car to have any trouble.
Do you have any advice for me? Is there any way out of this mess? Is it possible to request the photos from the speed camera to make sure that they didn't accidently fine the wrong person? Is there a way to buy myself more time (the first ticket is due in a week)?

Thomas

PS: It must appear to you that I'm a reckless racer, however, I would consider myself as a safe and foresighted driver who generally tries to keep under speed limits and obey all rules. I never had ANY incidents in Austria (since I got my licence 8 years ago).