Only Fiction I can think of off the top of my head is Sir Walter Scott\'s: \"The Talisman\".
(Available on Project Guttenburg)
But there are a lot of books set around the Court of Richard, Couer De Lion (LionHeart).
Have a look at the works of Bernard Cornwall as I\'m sure he has written a couple around set that era.
There is a book, must be about 30 years old now (plus), written from the point of view of a Jewish soldier defending Jerusalem from the seige of Crusaders. Was an interesting and differing read. Just wish I could remember the Author and Title.
Edit:
Look up the Osprey books as they are a good historical insight into the battles and uniforms.