My friend just leave here last week,just as a remind, you must only get tax refund for over $50 on each purchase...i.e. just make the receipt for over $50. After you fill up the form from web, you should go to the office at airport to apply for tax refund before luggage check-in. After they check for the receipts, they will stamp on it and you have to mail it to another address in order to get the cheque.