I have to say this story sounds very intriguing. It's right up my alley.
Check out Joe Martino's book Way of the Gray!
The Thirteenth World: Book One
The Way of the Gray follows the life of Garrüdd the Gray, formally Garrüdd the Red, A warrior born and First Lieutenant to Medjekydn, King and Lord of all the Lands of Rofalsmyr.
With much of his life behind him, half of which was in exile, his wife now dead, he embarks on a quest to slay an ancient dragon or die in glory and enter the halls of Valhalla.