The Forest Hozen become a permanent faction for Horde players, so they will only be able to pick this pet up before completing the quests that turn them friendly. Alliance can pick one up anytime they desire. I'm working on a permanent Horde version atm to.
Directions for the text readers
Go to Sliptail Pits and aggro a Slingtail Treeleaper hanging from a vine. Kite him up the river into Fox Grove. Once the phasing makes him disappear, run back into Sliptail Pits to make sure he leashed properly.