You can simply enter address or zip code, then a marker would place in the Google Map area accordingly. You can then publish the map and embed in your webpage. Please feel free to sign up a free trial account to test if it suits your needs first:
http://www.imapbuilder.com/gmap-builder/login.phpThe user guide of import marker by address is here:
http://www.imapbuilder.com/gmap-builder ... import.php