Guys, have you checked out CostCo? I dunno if there's one in SA or Brissie, but if you're in Sydney or Melbourne (or Canberra), it might be worth an enquiry and membership. It'll cost you ~$60 for membership, so just join up, drop your car off for the tyres and do some shopping while you wait. You'll easily recover the cost of your membership.
I'm seriously considering getting my next set from there, as they sell Michelin Pilot Sport 3s, Continental CSC3s, Bridgestone Adrenalins (and probably Potenzas too), and a whole bunch of other stuff there too. It's been about 3 months since I checked, but most of those brands were under $300 a corner for around 245s in an 18" diameter.
Oh, on that note, I probably wouldn't get a wheel alignment from there - I doubt they'd do a bad job with it, but I'd just prefer to go somewhere I trust...