In Nagrand, start heading to Windyreed Pass. On your way there, you should find the Nessingwary Safari, containing a small group of four people. In their little camp, there should be a crashed plane with an engineering supplies vendor near it. Look on the plane and you should see some snakes! If you get to Windyreed Pass without finding the Nessingwary Safari, or if you are just coming fron Terrokar, just follow the path South West.