I am in the Blackroot inn where Kitezel Pierce is supposed to be, but he's nowhere to be seen. I don't have his apprentice quest in my log, so I'm pretty sure I haven't talked to him. If he's not at that inn, where might he be? Is there anyone else that grants bow mastery in case I can't locate him?
This is a stupid question, but did you go to the right tavern? He's at Annabelle's Galley, at the bar, not the Sour Barnacle (where you find Dante). Perhaps it could also be an issue of what time of day it is? Wait a few hours and see. There is no other bow master, unfortunately, so I hope you find him!
It just occurred to me - does he only leave Blackroot for Caladon after being talked to by the player character, or will he go to Caladon anyway once the main quest has been advanced to a certain stage? I honestly don't know.
Next to Shalmo you'll see Kietzel Pierce, the Master Bowman. He'll ask you to track down a student of his named Dudley Crosston, and tell him that Pierce has moved on to Caladon. You can find Crosston in Dernholm.
If this is at Annabelle's Tavern, I must say that I've waited there for days and never saw the git. If there some other place he might be?