Google added a new feature called My Location to Google Maps for mobile phones. My Location works like GPS and shows you your location on your mobile phone.
If your phone already supports GPS, then it will use this information to show your location if it is not available it will try to approximate your position using the information from near by cell phone towers.
To find your location go to Google Maps on your phone and press “0”, it will show your location as blue spot. You may see a light blue circle if your location is not pin pointed. “The My Location feature is available for most web-enabled mobile phones, including Java, BlackBerry, Windows Mobile, and Nokia/Symbian devices.”
[Via Google Operating System]