I too tried looking for cloud sculpture--not much help there.
I think you need to have less drastic action in the wood. In other words, flatten things out a bit, soften any drastic changes in the contouring of the wood, and round off any corners to large radii. You need to have more gradual change in the surface. Take a look at the link to a photo:
http://www.williamolive.com/soliton/...ll%20cloud.jpg
See how things go gradually up and down, everything looks soft. So, if you "soften" up the edges of the "stones"--maybe even lose a few so that the a few of the "stones" are combined into a larger "cloud" amongst clouds. I think you'll get as close to clouds as anyone can carve in wood.
I think that carving clouds is one of those things that is a matter of interpretation--just like carving action in water. The more action you show that busier it will appear to be. But with clouds, it might be better to give just a "hint" of clouds.
Here's a few fun cloud-related links--they might even give you some ideas on how to achieve clouds--especially the last photo:
http://www.eglobe1.com/index.php/2006/10/02/cloud-art
I saw that flowing hair in the last one, and I thought "draw the lines, carve the lines". I guess easier said than done, huh?
http://www.eglobe1.com/index.php/200...5/weird-cloud/
Looking at the last one again, "who says clouds can't look like stones???"
BTW--what kind of wood are you carving?
Good luck!