I purchased a refurbished Power Mac G5 single 1.8GHZ machine from the Apple Store and 2 days after I received it. I noticed that Apple had dropped the price on the same refurbished computer that I purchased by $100.00. So I contacted Apple to see if I qualified for Price Protection and was told that since the price drop occured within 10 calendar days of shipment. A $100 credit would be applied to my credit card.
Here is what Apple has posted on their web site about their Sales and Refunds Policy.
"The Apple Store endeavors to offer you competitive prices on current Apple products and selected refurbished and clearance products. Your total order price will include the price of the product (on the day of shipping) plus any applicable sales tax and shipping charges.* Apple reserves the right to change prices for products displayed at the Apple Store at any time.
Should Apple reduce its price on any shipped product within 10 calendar days of shipment, you may contact Apple Sales Support at 1-800-676-2775 to request a refund or credit of the difference between the price you were charged and the current selling price.* To receive the refund or credit you must contact Apple within 14 business days of shipment."
Hope this helps.