I did as two I think of the replies above said, and abandond and got it again, I sat outside the road to the south for a while, put WoW on the bar, went on the internet, went to Thottbot here, read most of the comments, heard that I had just gotten attacked by undead, went back to WoW really quickly, and Vanished because I'm a rogue, and there they were. I think the above replies are valid, but only if nobody else had spawned them a before, as it's likely somone else tried the quest and couldn't find the courier and they just kinda went on, and you can't spawn them again until they're killed or they reach Tarren Mill and unspawn or however you'd say it.

Also for any rogues out there, another way to kill them would be to sap a guard, wait for the others to get a good distance away, kill the guard, and keep doing that till there are no guards left, and then take the courier, or just sap the last one and kill the courier and do what you want. You can't sap the courier because then all the guards just stop moving until the courier moves again.

O and my first character's name is Paladinpal, not the one I did this with, if you're looking at the "by" part. ^_^