For the past couple hours, the Kindle Store has been experiencing some rather odd technical difficulties. As you can see from the screenshot above, none of the titles listed are available to buy. But the really strange part is that this problem is only happening in the US. Other parts of the world can still buy ebooks.
What's even stranger is that if you click through to the listings, some of the unavailable ebooks are available again. And then they're not. While writing this post I have noticed the prices appear and vanish at least 4 times.
Luckily this only affects new purchases. I've tried several ebooks in my archive and I could read them via the Kindle Cloud Reader. And I wouldn't worry too much; Amazon will likely fix this in the next few hours. They've already responded to complaints posted in the support forums.
We are currently working on a website issue that is affecting the buy box for Kindle books. Some Kindle books are not displaying pricing information and show as unavailable. We anticipate the issue will be resolved shortly, and will update the network when it’s been fixed.