residence and working permit. (Istanbul)

Dear InterNations members. Can anyone tell me a way to get a residence and working permit after having lived in Istanbul for more than eight years? I have heard there are different rules for independent artists but I do not know which rules there are and where to get information.
I know I can go to the Aksaray police station for an "ikametgah" but that does not give me permission to work...

Hope to hear from you...