I agree with Claire on this...seeking a personal style is like trying to find happiness...it becomes a byproduct of doing something else. In this case of doing photography. I would go a bit further, however. There are things that one can do to enable the process...at least in my direct experience. The greatest single aid to personal expression is taking the time and expending a few brain cells in consideration of who and what we are...at the depth of our being...what meaning we give to our lives...what moves us and causes us to react with emotional response. In other words learning of ourselves.
I would go on to say that we, each and everyone of us, has a personally distinct and unique view of life. This has been the result of the totality of our lifes experiences. So we each will express that view in different ways.
There is a great deal that is not discussed within the realm of photography and more specifically creative artistic expression within photography. For instance where are the discussions of symbolism within photographic expression?
Where are the discussions on the depiction of symbolic form in contrast with photography of "known objects"?