Esa's Google Maps API v3 examples.
An Elementary Geocoder
Buttonless geocoding, second version
Just type and when happy, hit Enter or click outside text field.
Geocoding is requested by keyup event of text field.
The result is displayed above the text field.
Map is set to the result by 'change' event.
(IE doesn't trigger 'change' by Enter key.)
Request is not sent if the previuos request was sent less than 300ms ago.
Try this placename
Geocoder viewport visualized
Rent A Coder