Heightmap Voxel Terrain - HELP!

Hi, I am planning to create a game on a voxel based terrain. Why Voxels? It should be a strategy game where the player can transform the lansdscape (mining+building). I dont wanna a terrain generator but a heightmap terrain. My problem is that i am a script newbie. Are there some good sampes/engines/what ever? Or is there any other simple way to edit the landscape (building/mining)? It were awesome if some on could help me... THX ForceStudios