Head back out White Deer Creek Road toward McCall Dam State Park. Make a right onto Cooper Mill Road and climb the hill. You will come to the opposite end of Cowbell Hollow from which you parked. Head right on Cowbell Hollow. It will dump you out behind the cabin that you parked in front of.
The down hill on the side of the cabin is very rocky but this trail is pretty awsome even if you don't like the rocky stuff.