FedEx is half-way to what you want. They let shippers "notify" you, via email, that you've got a package on the way. The notification is actually sent from FedEx, and then you can sign up for notifications when the state changes, also via email.

So long as the shipper plugs in your email address, then they've got all the infrastructure and the rest is just hacking. I'd rather have them key things off of the email than the address, anyway, because there are plenty of scenarios where lots of people share an address (e.g., at offices), and I'd also like to be able to track things that aren't necessarily going to my house (I'll often use my work address for deliveries of boxes where I'd really rather somebody be there to sign for it).