Just thought I'd share with you a few books on the subject of the writer's voice I found extremely helpful during my MA in Creative Writing. They helped me in the writing of my second novel, When Skies Are Grey, my theme for this year.
Alvarez, Al (2006), The Writer's Voice, London: Bloomsbury Publishing
Edgerton, Les (2003), Finding Your Voice: how to put personality in your writing, Ohio: Writers Digest Books
Lamott, Anne (1995), Bird by Bird, New York: First Anchor Books
Nestor, Theo Pauline (2013), Writing Is My Drink, New York: Simon & Schuster,
The latter is my favourite - but these are all great for new writers. If that's you then have fun finding your voice!