Residence permit (Istanbul)

Hey everybody,
again I am counting on the spread of information here at Inter Nations ;-)
In my case it would be the residence permit. Some people told me that it is quite difficult for an foreigner to receive.
So that everybody here has the same problem I am asking:
What steps do I have to take, where to go, with which documents and what to pay. I am german and got recently married to my turkish girlfriend.
I am thankful for any help or links.
Thanks in advance!!