Why There Is No God is a Atheist Republic production outlining some responses for the common arguments against God. Not a very beefy book, it will take all of a day to read, but never the less a useful book. Another great resource for articulating and understanding  atheistic rational for your own lack of faith . Many of the thoughts you thinking as an atheist can be given names and faces in this book. I definitely recommend it as a good starting point for research into atheism, or if you want to get a better understanding of religious arguments for God.