Have they just put a normal come and collect notice in your letter box then? what does it say? unable to deliver? signature required? It is not unheard of for LEO to attempt a CD in AU with this method but 9 times out of 10 it's just a lazy postie who couldn't be arsed to leave your mail. However given your order is quite small as you say it should have been packaged in something that could have been left in your mail box ok. Have you contacted the vendor to see if they sent it requiring a signature by mistake? go and find out how the order was packaged etc first, if it was just sent via normal express post you may want to write it off.