I do most of my shopping online - most places will deliver to your place of work when a signature is required. Many e-bayers, however, will not so they have to go parcel post. My local post office hide parcels not requiring signatures in our woodstore and pop a not through the door to say that they have done so. However some carriers have left stuff on the doorstop. Luckily we live in a village and to date it has always been there when I got home.

As for Amazon, I have never had a problem and have always been sent replacements if things have not turned up.