Magellan 760 doesn't know where I live

My new GPS navigation system, the Magellan Roadmate 760, and for that matter Google earth, zillow, and just about everything else doens’t know where I live. It misses by a few hundred yards. Since I know where I live, it is simply a minor annoyance, I could easily turn the thing off once I am near home. What I wish to do is teach it my specific coordinates, call that “Home” and enter it into my address book. Does anyone know how I can do that? The manual it comes with is very skimpy and I could not figure out how do do this from it.

The following does not work?

I just got the 700, which is the same as the 760 minus firmware 5.0 and some newer maps. Is your home/address on a mapped street? Sometimes it tends to place the destination at the nearest crossstreet if it doesnt have a subdivision or shopping center mapped out.

No, actually my house is 10 years old, and off a private driveway. It says we are home when we are about 300 yards from the drive off the main road that turns up into our house.

I was hoping there was a way of saying home with just a couple of button presses. I will have to try the way described and see how it works.