It's PayPal you need to be talking to, I believe. (unless this somehow happened on the US boards in which case eBay Buyer protection kicks in)

But if the sale was made on this board (ie you had it listed here) and it was therefore sold on the au site (there have been instances where people log on to the US site to buy thinking this will buy them eBay buyer protection, but the system automatically registers the sale as having occurred on the site where the item is listed and is thus classified as being sold on that site)

anyway, i digress.

IF you listed on eBay australia and you are an australian registered user, it is through PayPal that this issue will be handled

You say you used the address supplied to you by PayPal - this is good.

Now, you just have to prove that this is the address that you used and all will be good.

best of Luck with it all.