The guy who wrote this back in 2004, came back last month to the message board to say this, among other things:
"The Cowman of Copalis Beach is being published in a compendium of Bigfoot tales by an author named Linda Coil. I gave her the the one time use rights to publish the story in her upcoming book. I am currently working on turning the story into a screenplay."
http://www.bigfootforums.com/index.php?showtopic=5530&view=findpost&p=445852
It would make a great movie. Unless it gets destroyed by the Hollywood moguls. As a Bigfoot enthusiast, I have had my hopes high on more than a few “in production” Sasquatch movies only to walk away from the theater feeling cheated and ripped off by another poorly done B-movie.