An update for anyone interested in this thread........
Laptop arrived today (along with a variety of other goodies) so I have one Xmas present covered.

Ordered on 27/11/14 from B&H Photo/ Video in NY who I have used to send various bits and pieces in the past but would not ship the laptop direct to Oz because it had a lithium battery.
I joined MyUS.com (as recommended by SamR) which is based in Florida and acts as a consolidator for shipping to Au. Easy to join - they have 3 membership levels and I chose the middle one (Premium) which has a once-off joining fee of $US20 and $7 per month / $60 per year. With Premium level membership you can have multiple orders shipped to MyUS and they will check and photograph the contents against the supplier's invoice on arrival. They will then re-package your various orders into one for cheaper shipping and on-send to Oz via FedEx. Premium also gets you cheaper shipping rates (around 15-20% off) compared to std. membership (which doesn't get you consolidation of multiple orders). I decided to pay monthly so I could cancel anytime if I chose to.
Both the suppliers I bought from provide free shipping within the US and despite it being the busy Thanksgiving /Black Friday they only took 2 days to arrive at MyUS. There was one as-yet-unresolved stuff-up by MyUS in that my shipping request was initially confirmed but a day later I noticed that one of the packages was "withheld pending review". I emailed them to hold all 3 packages until they could be shipped together (didn't want to be up for 2 shipping fees) but soon after received notification that my order was on its way without the 3rd package! Doh! Shipping cost was $US112 including insurance.
It then turned out that the 3rd package was "pending review" because they have lost it. Thankfully it was the least important one of the three (only contained some camera accessories) but all I have now is a photo to prove they did have it but now they don't. They tell me they are hopeful it will turn up with 5 or 6 days but I think that by now it's already in someone else's Christmas stocking.
Tracking the shipment's movements was easy using the FedEx tracking number (took 2 days from Florida to SYD). The FedEx Customs broker in SYD then emailed me the GST/duty amount to pay and it was released for delivery once I sent proof of payment. Then took another 2 days to be delivered to the Mornington Peninsula (6 days ahead of the estimated delivery date).
Interestingly, I expected to have to pay for "dangerous goods documentation" because of the lithium battery and even emailed MyUS to warn them about it but I was not charged anything other than shipping and insurance ($2 per $100 value) and when the laptop arrived the package only had what appeared to me to be standard labels attached and no mention of "dangerous goods". It seems that the lithium battery "problem" isn't of any consequence for the shipping agents.