Edmonds is a fantastic place to fish for Lings, and about as far south as I would fish for them in the sound because they get a good flush through there. I dont think I'd eat a ling out of Elliott or Commencement bays.

The best way to fish Edmonds is to hang about 300' away and to the south from the ferry with a horse herring rigged, then jaunt in as the boat leaves and drop your herring in the wash at the last set of pilings. Drop down to the bottom and mooch for a bit, because it seems the lings sit in there looking for wounded bait falling from the ferry wash. WHAMMMO!
Be sure to get out of the way of the returing ferry, you usually have about 10-15 minutes between departures and arrivals. Dont get too close or they will yell at ya or call in the CG to pay you a visit.