I found him at the U-bend between Prydwen Bridge and West Downs. Standing just to the left, a few meters up the hillside. My mistake was not completly reading the quest beforehand so dumb as I were I killed him rather then speak to him /sigh...
Found him again 3 minutes later walking on the right grassy area laying before the bandit camp in the hillside. As stated from others, he walks close enuff to the road for you to see him from horseback.... your own or a transport.
Edited, Apr 22nd 2015 5:00pm by Jarah