Templars in Fiction:
Robyn Young has written a triology on the Templars - Brethern, Crusade & Requiem.
Micheal Jecks has written about 30 books with the Templars (I am a bit biased as he is one of my favourite authors).
Raymond Khoury - The Last Templar, The Sanctuary, & Templar Salvation.
Jan Guillou - The Road to Jerusalem, The Knight Templar & The Kingdom at the end of the road (also made into a film - Arn).
Steve Berry - The Templar Legacy.
Umberto Eco - Foucault's Pendulum.
Paul Doherty - The Templar & The Templar Magician.
William Watson - Last of the Templars.
Fact: (or as close to it as we can get)
Piers Paul Reid - Templars: The Dramatic History of the Knights Templar, the Most Powerful Military Order of the Crusades.
Malcolm Barber - The New Knighthood: A History of the Order of the Temple; The Trial of the Templars.
Sean Martin - The Knights Templar: The History and Myths of the Legendary Order.
James Wasserman - The Templars and the Assassins: The Militia of Heaven.
Edward Burman - The Templars: Knights of God.
Regine Pernoud - The Templars: Knights of Christ.
Sharan Newman - The Real History Behind the Templars.
James Anthony Froud - The Knights Templars: Their Rise and Demise.
Mythos & Legends:
Lynn Picknett & Clive Prince - The Templar Revelation
Erling Haagensen & Henry Lincoln - The Templars' Secret Island
Barbara Frale - The Templars & the Shroud of Christ; The Templars: The Secret History Revealed.
Karen Ralls - The Templars & the Grail: Knights of the Quest.
Peter Partner - The Murdered Magicians: The Templars & Their Myth.
Frank Sanello - The Knights Templars: God's Warriors, the Devils's Bankers.