Bush Point can be good for Salmon. There are some strange access rules on the beach that make it so that it is really only a decent option when the tide is out. Otherwise there is only about 30 yards of beach that allows for a back cast.
The state park @ Possession Point is closed weekdays for construction on their seawall. Per the ranger, construction will likely go thru September (bummer). It is open on weekends. If you want to fish during the week, you could try the beach @ the Bait Co. (small beach, but free) or @ the Possession Beach Waterfront Park (north of the boat launch). If you are on the Island, get a copy of Getting to the Water's Edge on Whidbey & Camano Islands. Check the stores, it is worth the price.
Paul, good to know! I'm on whidbey for the weekend and was going to head down there for a bit this evening. Decided to save my time for the morning.
HFF- I'll most likely be at bush point tomorrow morning (early)if you want some fly flinging comraderie.