Roaming Bowyers can be found all over Osteth, selling their wares (missile weapons and fletching items) in lonely cottages or other outskirt locations.
See:
- Roaming Bowyer (Outskirts Bandit Castle) - 71.8N, 38.0E
- Roaming Bowyer (Outskirts Rithwic) - 11.3N 55.7E