Free: Contests & Raffles.
The Longview area has loads of them
Capital Lake here in Oly has them. There were a ton in Eugene. I used to shoot a few while duck hunting, and my dogs got a few. 2 dogs and a nutria make one hell of a racket while battling it out the bushes!
All up and down the Yakima River, closer to yakima/terrace heights the more of them you will find