rune of teleportation help

So im new when to the teleport trainer in darrness. night elf city I recived the training but have no idea where to buy the rune please help
You buy it from a reagent vendor. Ask a guard in any major city.

Cenarion Enclave, northern Darnassus

Once you get close you can see the vendor on your minimap if you have vendor checked.
Uh... Miiiiight wanna check the dates of the posts in a thread before responding in the future, Jhondran.