(Not sure if this is on topic or not...)
I've been fiddling with blender recently, and I discovered that in the current version, you can make your own fractal height maps. Here is how it is done:
1. Create a grid, with a lot fewer divisions than the final map will need.
2. Optional: Add mountains, etc. with the proportional edit tool.
3. Use fractal subdivision to fractal it up and double the number of grid squares.
4. Repeat steps 2 and 3 as much as needed, probably 2 or 3 times.
Further tips:
A. You can build nice canyons, river valleys, etc, and touch them up at each step along the way.
B. If you are happy with some parts of the grid, you can deselect those edges, to reduce the polygon count.
C. This is also a neat way to make rocks (start with a sphere), crumpled up paper, etc.
Fractal subdivide is SPACE-Edit-Edges-Subdivide Fractal; the number is the magnitude - I would start with 30-50.
Wikibooks has a great blender tutorial (half done of course, but the first half is great...)
Sw.
