Aki ta.. 
   <?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
    die('Could not connect: ' . mysql_error());
}
 mysql_select_db('mydb');
 
 mysql_query("INSERT INTO mytable (product) values ('kossu')");
 printf("Last inserted record has id %d\n", mysql_insert_id());
 ?>
 
 http://ve.php.net/mysql_insert_id
 
 mysql_insert_id — Get the ID generated from the previous INSERT operation 
Description 
       int 
mysql_insert_id     ([ resource $link_identifier   ] )
        Retrieves the ID generated for an AUTO_INCREMENT column by the previous     INSERT query.