multiple queries, one transaction

I would like to get the itemID number (autoincrement) of the last insert. (Insert order, get last orderID number and use it elsewhere.) I'm having trouble understanding how to do a transaction in mysql/php Code below: $conn = mysql_connect($dbhost, $dbuser, $dbpass) or die ('Error connecting to mysql'); $dbname = 'mail'; mysql_query("BEGIN"); // starts the transaction mysql_query($query) or die('Error, insert query failed'); mysql_query($query2) or die('Error, select query failed'); $query = "INSERT INTO orders (orderDate) VALUES ('2005-05-17')"; $query = "SELECT max ordered FROM orders"; mysql_query($query) or die('Error, insert query failed'); mysql_query($query2) or die('Error, update query failed'); mysql_query("COMMIT"); // ends the transaction mysql_close($conn); ?> thx