A useful blog series by Micheal Kruger about the canon of the New Testament, that is important for evangelism with atheists, muslims, and others attacking the canon of the New Testament:

http://michaeljkruger.com/the-complete-series-ten-basic-facts-about-the-nt-canon-that-every-christian-should-memorize/

another series of blog posts by Micheal Kruger about the NT canon, addressing common misconceptions about the New Testament Canon:

http://michaeljkruger.com/the-complete-series-10-misconceptions-about-the-nt-canon/