Normal maps?

I’ve a problem, if I want to use bumpmaps and other nice looking stuff I need normal maps, but I don’t know how to build them. I think I could import BMP for ex. and use RGB values per pixel as 3 vector coords, but I don’t know how to draw the normal map. I could calculate different RGB values per angles, but that sounds crazy! Maybe someone knows beter way to create normal maps.
By the way, what’s about normalization?

Hi! Stay calm boy! Go to www.nvidia.com there you have a plugin for Photoshop to generate normal maps from textures. Not so hard, hein ?

Hope this helps.
Bye

Thanks, there was also comand line generator which seems more practical to me.

Look at Tenebrae’s (that q1 mod) sources.