Anyone have any experience of using Amazon's A-Z Guarantee?

So I ordered a S3 on an amazon.de marketplace seller about a month ago. The seller had all positive reviews so I thought it would be fine. The order never arrived, but my account was charged, and I checked today, and all the reviews in the last month say that the order never arrived.

It looks like the seller has gone out of business, or that no one is monitoring the account. The reviews say that they aren't responding to emails.

Does anyone have any experience with this sort of situation, and am I likely to get my money back? If so, how long is it liable to take?

Here's a link to the sellers page http://www.amazon.de/gp/aag/main?ie=UTF8&asin=&isAmazonFulfilled=&isCBA=&marketplaceID=A1PA6795UKMFR9&orderID=&seller=A3EH957S58IQRQ