Take this for an example: I ordered some replacement parts, back in September. They were sent to me via Australian Air Express - an Australia Post offshoot. They were marked for delivery on 21-9-09. But they were never delivered. Not a word, dead silence, nowhere to be found.
Today 30-11-09 I received a card through my door telling me that it was a "Final Notice" to collect the package from the Fitzroy South Post Office. It may be a final notice, but it's also a first and only notice. The parcel has been sitting at Fitzroy South Post Office since 21-9-09. Today they decide to tell me about it.
So when you see those stupid ads something about "Australia Post - we deliver", you need to understand that there's a word missing. The word is "don't" Australia Post don't deliver. At least not for over 2 months.
Also please take a lot of care in interpreting both the "Air" and the "Express" in Australian Air Express. There's nothing express about two months.
If this were a one-off occurrence I suppose I might not have written this. But it is not. I get mail delivered for every address under the sun - just not mine. Collingwood Post Office can take up to a month to get around to putting a letter in my PO Box.
Parcels are never delivered, the driver simply drives up to the door, doesn't knock and just puts a card through the door - I've watched them do it!!
Do something about finding some customer service and try to learn how to deliver stuff Australia Post. At the moment you don't do either thing.