Why swim over to Sunwell Isle, of course!
Here's what you need to do, in six easy steps.
1. Make a priest.
You want a level 1 Blood Elf Priest so you can heal yourself through the fatigue.
2. Take your priest and look at the map.
See that big new island to the north? That's where you want to go.
3. Head North
Go north towards that big new island, and that means you're going to need to swim. As you can see from my screen shot below, you can actually see the island off in the distance.
4. Take a few hits
Once you pass into the dark waters, you'll start to see the fatigue bar pop up. Once that bar hits zero, you'll start to take damage, about 8 per second as a level one priest.
5. Heal yourself
When you begin to take damage, wait until you have about 50 percent health. Stop and heal yourself. You will take damage from the fatigue, so the heal with be interrupted a bit, but it will eventually go off and you'll find yourself at full health. As soon as you're at full health, start moving again.
6. Rinse and repeat
Repeat step 5 until you get to the new area!
When you're doing this, you will see many dead bodies of failed attempts along the way. But doing this little trick with a priest isn't too hard. I was able to make it on my first try. Mana will get low, but hopefully when that starts happening, you'll be really close to the isle.
Check out our gallery of a Level 1 Priest going to Sunwell Isle to see more screen shots of how to do this. If you don't want to try this just yet, you can still get a peek into the new Sunwell Isle by checking out our picture galleries of Sunwell Isle and 2.4 Goodies.
Oh, and when you do get to the Isle of Quel'Danas, you're greeted by the plethora of Level 70 mobs that insta-kill you. Have fun!
Minor Update: Just to clarify: while there is a flight path outside of Silvermoon City, it does not work for those of us that are level 1.
Updated Saturday, February 15th, 2008: Apparently the Blizzard gods didn't like my guide. They've placed a large invisible wall around the island, and it's not impossible to swim over to Quel'Danas. You can still be summoned by a warlock, or if you're level 70, fly out from Zul'Aman or Silvermoon City.