Horde only need one catch in Stormwind to complete The Fishing Diplomat. There are no rare fish to catch. There may be cheap wow gold need to enter the city of Stormwind at all: The achievement has been completed by fishing from Stormwind Harbor.
Fly to Grom Gol Base Camp in Stranglethorn Vale, then ride/swim north up the coast to Westfall. Ride along the coast to avoid most Alliance in the area. At the northern border of Wes...