Okay here is my long awaited(if not with bated breath) tutorial on the Burpwallow method of noise editing for terrain creation. To start with, I will work entirely in Photoshop. Later I may look into integrating Wilbur into the workflow.
1)Black/White Clouds and lots of Black/White Difference Clouds. This may have lots of islands where you want water and wet places where you want land.
2)Create a Linear Light layer for raising hills and mountains as well as for some lowering.
Layer: Linear Light
3)Create a Pin Light layer for creating flat lowlands. This can also be used to create flat underwater areas.
Layer: Pin Light
4)Create a Multiply layer mostly for lowering areas below water. This can be used in combination with the Linear Light layer to create a less flat sea bottom, but I really didn't do this.
5)Create a Threshold adjustment layer for reference and to create the sea level mask. In my case, I found a threshold of 42(on a range of 0..255) worked well. YMMV. This will be turned on and on frequently during HF editing to allow you to make the shoreline look the way you want it as well as to keep the HF looking good.
6)Using a fairly large soft brush, I painted a fairly bright shade of gray to the Pin Light layer to raise up low areas where I want land. This results in flat, alluvial-looking lowlands. Try experimenting with darker grays to create underwater shelves and the like.
7)Now, on the Multiply layer, I use a darker gray brush(RGB < 128) to paint down areas where I want sea.
--- Because the Multiply blend mode reduces relief(not just heights, but actually difference in height and therefore slopes), this method can be used in combination with Linear Light(basically, add/subtract) to flatten out land areas. Simply use multiply to reduce relief to the desired flatness, and then use Linear Light to raise the area back above the sea. I haven't tried this yet, it might prove superior, in some ways to Pin Light, but it would require closely coordinating work in the Multiply and Linear Light layers to pull off successfully.
8)Some areas on land, I paint hills in on the Linear Light layer. To do this paint in the desired areas with a gray color greater than RGB 128. A level of 128 is effectively zero for Linear Light. Given that, you can also paint in depressions in Linear Light by using a gray darker than 128.
9) Now that we know how the three layers work, we can go back and draw into them, raising, lowering and flattening the terrain until we have something we like. Basically wash rinse and repeat.
10) This is less of a step than an opportunity to give some tips.
First tip, always start out with large fuzzy brushes. You can get really nice effects with some very broad impressionistic strokes, whereas very tight, small strokes can obliterate the noise and leave very visible fingerprints.
Second tip. At the beginning of this project I drew into the layers using a fairly opaque paint brush in Normal mode. As the terrain starts coming together, reduce the opacity of the brush and try other paint modes. I had great success with Linear Light and Multiply to just sort of tweak my existing edits. This is also a good idea if you choose to do some fine editing with small brushes. Still... you should avoid HARD brushes.
Another tip. I didn't do this, but you could use Layer Sets instead of Layers. Then you could be more non destructive by applying edits as layers within the Multiply, Pin Light and Linear Light SETS. Hmmm... Might this way lie madness?
After working with this, you should have a decent terrain to start working with. Next up, makin' it purty!
BTW, I'm posting up a copy of my psd for reference. It's kind of a pig, though, so if folks have trouble uploading it, I might have to put up a reduced res version.