I have a book entitled "The Joy of PI" by David Blatner which tells the story of the search for the complete value of the relationship between the circumfrence of the circle and the radius. It also lists PI to the millionth digit. Takes one hundred thirty pages in a book slightly wider than a Reader's Digest volume.
You can also experience the joy of pi online. The website is
here. Oh, by the way, the one millionth digit is '1.' I knew you wanted to know.