Do you have the hard neck (and time) to go round all the neighbours asking them if they were the ones who took in the parcel you were waiting for? Take the name of the person who signed to show them, they may recognise it.
Maybe it was a gardener or tradesman who was at a neighbour's house when it arrived? It could be a false name, of course, anyone intending to keep it would be a bit dim to sign their own name.
The delivery men should have put a note through your door to say it was at number 21, or whatever. Kick up a fuss.