What is the best program to do these? list seperate if there are programs that specialize in only one of these. but i need help

for which engine? what file format you need the map in? I used Hammer Editor to create levels in BSP format.

any good, complex, 3d modeling program should do the trick. 3ds max and maya are very nice and complete tools, however there is blender if you cna stomach dealing with the gui.

Freeworld3D
3D World Studio
T.E.D.
Panorama

It depends on what type of worlds you plan on creating and how you plan on producing them. Do want to use mostly heightmaps or static meshes for the terrain, or a mix of both? This question can probably be best answered if you know how large (scale) the level(s) is going to be and how detailed (mesh resolution) you want it to be.

If you want large scale and simpler environments a program/editor that can produce and manipulate heightmaps with relative ease and flexibility will be more important. If you want very complex and detailed environments then you'll be better off creating static meshes in Maya, Max, or Blender and importing them into the game engine/editor you plan on using.

To get started with something relatively simple I would recommend heightmaps - then just choose your favourite paint package to create them. As for loading and using the heightmaps there are plenty of tutorials out there to show how it can be done (I thing NeHe has one for OpenGL for example).

But of course it depends exactly what you are trying to do .. the terrain you need for an RTS will be different from that for an RPG or a first person shooter.