You can read at the following link an english transcription of a course of dogmatics by Metropolitan John Zizioulas:
http://www.oodegr.com/english/dogmatiki1/perieh.htm
It is quite readable and understandable for anyone. In my opinion, it's the best presentation not only of orthodox dogmatics, but also of Orthodoxy...
I suggest to start your reading from Part C. ON COGNIZANCE AND FAITH.