Well I think that Neistadt dealt with some of the lines in his book on the Catalan. 
Also notice that black might transpose to the English opening or the (semi)Tarrasch defense.
1.Nf3,d5 2.g3,c5 3.Bg2,Nc6 4.d4,Nf6 5.0-0,e6 

For some of the lines perhaps you should consult a book on the Grunfeld!

I try to build a repertoire that consists of a mixture of the Reti-, Englishopening and the KIA. I dont like the Reti Advance variation, 1. Sf3 d5 2. c4 d4, so that I will play 2.g3. Also I dont see any advantage for white if Black plays the white part of the KI, 1. Sf3 d5 2.g3 c5 3. Lg2 Sc6 4.0-0 e5. So my choice is the Grunfeld as white,1. Sf3 d5 2.g3 c5 3. Lg2 Sc6 4. d4 , what could also lead to a Catalan. Do you know any good players, who use the grunfeld as white or any books or other sources, that explain this variation. I own all the recent books about Reti and KIA and a few about the english, but I never foiund a book about that system.
I would also appreciate, if someone of you would share his own experiance with the grunfeld as white.

Thanks for your help