So far, what I have done is using this way to add into my specific content type. For the map_page content type, I adde the below two line of code in page--map_page.tpl.php.
drupal_add_js("http://maps.google.com/maps/api/js?sensor=false", 'external'); $scripts = drupal_get_js();
Is there any other better way? if possible can give some example, currently not really understand well...