sharp arrows

Does anyone knows where you can get the skill to make sharp arrows (also known as deadly arrows)

I saw a recipe for sharp arrows in Armon's shop directory. He is located between Reddock and Montera, close to Reddock.

Yeah, but that's just the recipe not the skill. I think 'they' forgot to put a trainer for this skill in the game. In the end I did a 'teach It_Perk_SharpArrow' just to use the recipe.

Saw the skill in Silden today. It's a book called "Special Skill: Sharp Arrows". Book and recipe were available at the hunters' huts outside the town.