I received an item that I didn't buy or win!

[seniorgrognard]

So, this is different. I shop on eBay all the time. I just received an item from an international destination - a PO Box with no name or other information - that I did not purchase. The item(s) are they same type as I always purchase, so it's not likely random. Any idea how I could track down the seller? No item number (it might not even be an eBay auction), no name... just a PO Box. Strange. Groggy