Sounds like your drive has thrown a cog. (or the cog is worn down)
In terms to the value of fixing it, I would only probably bother if it was a launch console.
Not sure who repairs consoles in Adelaide, but I would start by looking for businesses that mod consoles. They may not fix it, but they should know who can.
Contact SONY and ask what they charge to repair the unit. They will be more expensive, but if you have a launch 60Gb model, I would get them to repair it. Those backward compatible consoles still fetch a hefty price on e-Bay.
Sounds like you PS3 is still "working" so before you send it to anyone (or chose to dump it) get an external USB drive (formatted to FAT32) and back up your hard drive mate.
Sorry I could not be of more help
Edit: As I was typing this, I noticed this add on the TOG web site. http://www.repaircentral.com.au/repa...station-3.html
Although in Sydney they might have some advice or a contact in you neck of the woods. (They also claim nation wide repair).