Great idea! I grew up sailing, and though I was a bit pissed at my parents for not allowing me to pursue my dream of professional motorcycle racing, and that we sold most of our bikes and got into sailing(following my father's old dream), I soon grew to love sailing. Non-motorized sport, cute women in shorts and bikinis, and the feel of the boat responding to a good breeze. Nothing quite like it.
Take a couple of lessons somewhere. It will increase your knowledge a hundredfold, similar to getting out there and climbing, rather than just reading about it in Freedom of the Hills(though the book you picked up is a good one, and certainly a good place to begin). Firsthand experience adds up to knowledge.
I recommend looking around for a used Lido. 14 ft. of fun. Might take you awhile, as they are popular boats, but perfect for lake/sound sailing. Easy trailerable boat. Probably a Lido club around Seattle. Good, responsive, beginner friendly boat. As a previous poster mentioned, skip the rowing-sailboat idea. Learn to read the weather and the wind(maybe you already know how from climbing), and skip the windless days. Usually you can sail in even the most gentle of breezes, but you'll learn to tell when it's a good day for sailing.
Peruse Craigslist, and you'll start to get a good idea of boats.
Happy Sailing, man!