One week ago, Apple (Stock Quote: AAPL) announced that it would give out free cases to all iPhone 4 owners and offer a refund to anyone who has already purchased the case, which typically costs $30. This giveaway comes in response to thousands of complaints that the phone loses its reception when users hold it a certain way without a case.

Apple is now starting to make good on that promise… sort of. According to its website, anyone who has bought an iPhone 4 case from Apple online or at one of its retail stores will automatically get a refund.  Unfortunately, while the refunds will come quickly, there is no telling how long it may take for some customers to receive their new free case.

As Steve Jobs said during the press conference, the big problem is that customers have bought more than 3 million iPhones so far, yet the cases have been less available since the shape of the new phone is different than the previous model. At the moment, Apple’s online store lists all of the iPhone 4 cases as being “currently unavailable.”

We called up an Apple Store on Boylston Street in Boston to see if they had any in stock and were told by a customer service person that they don’t expect to get any cases until at least next week. The representative suggested that we could download the app and order a case that way, but he said it might take 3-5 weeks to actually receive the case. Alternatively, he suggested that we look for a case at Radio Shack or Best Buy, though he was unsure whether these cases would qualify for the refund. Apple’s website also offers no statement for whether these stores participate in the refund.

Apple did not immediately respond to our request for a statement.

Those who purchased the case on their credit card should either have their refund already or by the next billing cycle. (You can check the status of your refund here.) For those who purchased the phone in cash or with a gift card, you will have to go back to the store and show them your receipt to get the refund. Meanwhile, anyone who purchased the phone at an AT&T (Stock Quote: T) store will have to mail in a form to get a rebate.

Going forward, if you have bought the new iPhone or plan to buy one and want to get your free case, you will have to download a free app onto your iPhone called iPhone 4 Case Program. That app allows you to register your serial number so Apple can make sure no one gets more than one case per phone.

Still, the free case giveaway seems to be improving customer spirit. As one user wrote on Apple’s website, “Personally, I don’t have a problem with reception. But I’ll take a free case!” That must make Apple feel good since the whole gambit is expected to cost them $175 million. Sure, that won’t exactly break the bank for them, but it’s still a significant amount of money.

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