Does anyone know some Tutorials about Lighting Mathematics?
Is there anything what I need to know before I start with OpenGl Lighting?
There are probably dozens of them on the net. Here’s one (see chapter 4):
http://duriansoftware.com/joe/An-intro-to-modern-OpenGL.-Table-of-Contents.html
You should make a descision up front; fixed function or shaders.
By far the best & most flexible is the shader approach - but ensure you use your own uniforms rather than relying upon fixed-function uniforms like gl_NormalMatrix. Reason being you can define your own lighting calculations and you don’t have to perform usless calculations such as inverse model view matrix just so you can use the normal matrix and variants.