See Wind stone for information on summoning the Dukes and Lords, who drop rare and epic items. There is a 'hidden' chain of killing which lets you summon them.
Also see Cenarion Circle Reputation Guide.
-  The New Frontier (Darnassus, Ironforge, Orgrimmar, Stormwind, Thunder Bluff, Undercity)
Emissary Roman'khan series
-  Goldleaf's Discovery