I don't know any sites, but I've been programming and making sounds all my life (aside from being a producer and a crazy guitar player).
If you want to know how a specific sound was made - you can always ask me.
I like a challenge.
As for kraftwerk and William Orbit...
They aren't all that complex. In fact most of their stuff is pretty straight forward.
That's just an opinion of a knob tweaking
psycho, so if you do find Kraftwerk all that great - don't listen to me, listen to Kraftwerk instead!
-ED-