Have you contacted the courier and asked if they remember where they delivered your item?
There have been cases here where AusPost for example remembered that the address was not the address the item should have been delivered to.
Did you use PayPal to pay? If you did, you could still open a case with them, but first you need more info from the courier, as PayPal will close the case in the seller's case too if the tracking says delivered (to the right suburb).
