I fond 2 great grinding spots. One in Hellfire Penisula (Pools of Aggonar) there are mobs with ~ 500 health who give XP as regular monsters. And other in Zangarmarsh(a little island north of Ango'Rosh Grounds) mobs with skulls elites and boss on their name but with very litle health and the most important they give ~ 6000 XP each. I have hunter 65 and can kill them.
I wish you nice leveling, bye.