I read somewhere that clay in the first build of minecraft is as rare as hens teeth, so we should expect the resource to be a little more common in the next update.
Coincidently, you may have noticed that the map generator does not always give you loads of great resources. For example my current map has zero cactus. So my advice is, load up a new map, check the resources, if it floats your boat save it and continue using it :)
Still not ginger.
Now in my 37th regeneration.