Update 2
Mesh editor 99% Pretty much finished.
Height map maker 99% Pretty much finished. Im not incredibly happy with it, but there's only so much you can do with image manipulator.
Texture maker 80% Working model with decent functionality. It's actually working much better than I thought it would. Its limited to 4 textures due to the fact Image manipulator wont capture all of a tilled background object, so for now the texture must be the same size as the map.
It shouldn't be terribly hard to use, but I'll make a few tuts to make things easier. The height map is probably the hardest thing to figure out, so Ill make one tut for the app, and probably others for Gimp.
I also plan on setting up a website to host the tuts, and perhaps set up a mesh sharing thing there as well. Well not just mesh's I want to add a bunch of textures to use as well.