Can anyone point me to secular sources on the net about how different books were selected for the bible? I can only find thousands of religious sources online.
What is wrong with religious sources? You are asking why Christianity adopted particular books, the Christian explanation is a valid historical facet of your question. For example the Catholic Encyclopedia has a pretty good discussion of the formation of the New Testament canon that traces the history and offers some account of how Christians differed in their views of the New Testament's books