what is the best and simplest way to create a 3D landscape?

Heightmappig definetely, an 8 bit greyscale bitmap where black is the lowest and white is the highest.

kool, theres a tutorial on nehe isnt there? know of any other good tutorials on the subject? oh, and is it hard to texture map to a height map?

A few good height map tuts here:

http://www.gametutorials.com/Tutorials/opengl/OpenGL_Pg4.htm

You can also use ipicture to laod the map (so you dont have 2 write ur own load routine) - just make sure it doesnt make a texture.

trent polack - focus on 3d terrain programming

best you can find/all in one