Where can i can that plain blue sky with some nice white clouds sky texture? Is it stock or do i have to dl it?

Look in your gfx/env folder. I think it's called greenfields or something like that.

grnplsnt is a good skybox. It's green, and pleasant.

... and overused :) Let me know if you are looking for a tutorial to create skys with terragen ;)

For a rainy sky, try killertomato.

Originally posted by Mythic_Kruger
... and overused :) Let me know if you are looking for a tutorial to create skys with terragen ;)

Yes Please :D

You dont need any special tutorial. Terragen using is very simple like every landscape generator based on shaded 2d bitmap.
1) You randomly generate base bitmap. It's like height map in atlas. Try some settings to get higher/sharper or lower/softer landscape. You may change heights on image with clicking mouse (hills/lakes).
2) Set sky settings - clouds, etc.
Best is to try different settings all above options make quick/low quality render to see effects.
3) Set sun color/atmosphere/sky colours. This is real tricky to get right effect and takes most of time designing skybox. Of course you should put similar or the same color settings in light_environment.
4) Put camera somewher with good view.
Then:
Make 6 renders, setting camera angles at:0, 90, 180, 270 horizontal and -90 and +90 degs vertical. Horizontal angles are relative to initial camera position of course.
That's it.

PS. For getting good right sun colour atmosphere settings get nice photo of real sky you want to get in your skybox the try to match Terragen settings to it.

PS2. If anyone knows easy way to make city landscape I would like to know how to do it. :)