Originally Posted by cig

Exit Ironforge and head east. There's a fork in the road as you come down the hill. You can take either, but the right fork should be the easiest. It will take you up and around a frozen lake. GR is built into the hillside and will be on your right side.

http://www.worldofwar.net/cartograph.../dunmorogh.php
It's in the area marked Leper Gnomes.