Not mentioned in the Cross-faction pages are a great way to reach Stormwind. All it takes is a fast mount and a shaman(since shamans have the water-walking ability) or a water-walking potion.
Fly to Zoram'gar outpost (that's in Ashenvale, Kalimdor). Once there, travel north along the beach and when you reach the end of the beach, apply the water-walking potion and hop on that mount and ride further north on the water (alternatively, apply the potion when you land and travel north out in the water from the beginning). When you come to Auberdine (Alliance territory), swing out so that you are waiting for the Stormwind boat. Thats the southern one, the only boat w/ guards on it. Position yourself a good bit ahead of the boat and when it starts to take of, run ahead of it so that you will reach its teleportation point at the same time as the boat does. This will let you go along for the ride, and voila: You are outside of Stormwind Harbour. Since I've only done this once, I don't have the coordinates for the teleportation point yet, but I'll try to get them the next time I make a fishing trip to Stormwind.
