Speak with Earthmender Torlok at the Altar of Damnation in Shadowmoon Valley.
The elements need your help, [race]! Shadowmoon Valley has been subject to unspeakable evils. The spirits remain tortured to this day. Many are enraged and unwilling to commune with the Earthen Ring.
Help this world heal, friend.
Directly northeast of Wildhammer Stronghold you will find an area known as the Altar of Damnation. Make your way there and speak with Earthmender Torlok.