I think part of it originated from realizing that many of god's rules were impossible to follow. Also that some of them are very unpleasant to attempt to follow. Reason told me that for god to give me rules that I can't follow, for me to then feel guilty about not following them, well he would be more of a sadistic freak then an all good god.
From there I listened to the audiobook version of "The God Delusion" from my local online library and later Hitchens-The Portable Atheist.
From there I listened to the audiobook version of "The God Delusion" from my local online library and later Hitchens-The Portable Atheist.