如果联系人页面仅由关联模板标识，则可以在meta key中查询模板名称为的页面_wp_page_template:

$args = array(
    \'post_type\' => \'page\',
    \'posts_per_page\' => 1,
    \'meta_query\' => array(
        array(
            \'key\' => \'_wp_page_template\',
            \'value\' => \'contact_template.php\'
        )
    )
);
$contact_page = new WP_Query( $args );

if( ! empty( $contact_page->posts ) )
    echo get_permalink( $contact_page->post->ID );