There's some confusion as to where it is, so here's the laydown =)

SFK is located in Silverpine Forest, which is the next zone down from Tristfal Glades and the Undercity

It's fairly in the middle of the zone, and just above pyrewood village. If you follow the road through, you'll probably find the village =)

Here's an idea of what you're looking for:
http://img.photobucket.com/albums/v18/Golden/sfk.jpg

Enjoy!
-Sorc from Frostmourne,
Bronze from Chromaggus