Last minute Christmas shoppers, take notice. Amazon has your back. The online retailer announced free expedited shipping on many items. Stop procrastinating and get your Christmas shopping done. Or wait a bit longer. The cut-off is tomorrow night anyway.Order by 8 pm PT on December 21 for free two-day shipping on the $79 Kindle, $99 Kindle Touch, $149 Kindle Touch 3G and $199 Kindle Fire. Amazon is already selling the product family at a rate of more than 1 million units per week and this offer will likely up that count. To take advantage of the offer, shoppers simply need to add the desired Kindle to their shopping cart.