Speak with Shindrell Swiftfire in Astranaar.
If you're fresh off the boat from Menethil, then the first thing you should do is... go to Astranaar. I'm sure an eager member of the Alliance such as you can do some real good there. Speak with Shindrell Swiftfire and offer your services.
But don't bother mentioning who sent you. Shindrell does not know me...
You are here to offer your services to the Alliance, <name>? We welcome the aid, for although its beauty remains... Ashenvale Forest is not the peaceful place it once was.