how to get the place marker's coordinates?

[maya]

Hi!
I have a geographic searching option in my homepage using php and MySQL database. I have maps with several properties (like title, publisher etc.) in this database, and a field contains the polygon coordinates representing the map's  corner points. If the user want to find a map with x,y (20°, 180°)coordinates write them into a textbox or click on the Google Maps, and with the mysql query will get how many map are about that area.

And I would like to make an other searching function using GMaps Geocoder, so it will be possible to search with the writing into the textbox the real address.
Could you tell me the following thing:
I using the geocoder sevice and the geocoder creates a place marker. How can I get the Place Marker coodinates  as a javascript variables (like x,y) without any click or other mouse event on the map? Because I want to give it further hidden to php script, and the user should see only the result of the query.

Thanks a lot!
Have a nice day!