I work on google maps. You can fix the geocode of your address from google maps itself. If the problem in your town is more systemic than "maps can't locate my road" or "maps misplaces my address on the road", please send me an email with some details and I'll investigate (but I don't work all that close to the geocoding portion of the service), rrenaud@google.com.
My main complaint about Google Maps is how it always assumes I'm in America. I live in Tokyo. My default location is Tokyo. I search for "Ginza". I get a sushi restaurant in Alabama.
If you're logged in there should be a "Set default location" or "Change default location" link on the left side, just bellow "Get directions" and "My places".
