at 13, my (soon to be) ranger was pounding on the Antonican Stag in Archer's Wood. At night, the gnolls come out in Archer's Wood and they're fun to kill too!
I think I was also still terrorizing the wolves and bear that wander around Sayer's cabin.
You might also still be able to smack the scarecrows outside the North Qeynos gate... if they haven't gone gray to you yet...
You might also find your way to the area near Oricle tower. There is lots of good foraging there and plenty of mobs for your level.