The old Ducks Head trail head is connected to the Jackson Ski Touring center's Troll Trail. The Troll trail connects the golf course area of the Ellis River trail to the Red Fox restaurant. Coming from the restaurant the trail is obvious. Make a left at the first intersection, and shortly after that the trailhead is obvious to the left. At first it is easy to follow, with some exceptional markings on trees, then not so easy. I've only followed it to the old Iron Mountain ski area, but my old maps say it continues.