I have always found it easy to find, even though I live in Michigan. Trips to San Fransicso always have one, two, or even three stops at the Toronado, where it is on tap. Then drive up to Santa Rosa, they have a lot on tap at the Brew Pub.

All kidding aside, unless you are in one of the areas blessed with good distribution, you have to work hard to find it. IIRC, you are not in one of the states they distribute to. Online shops may be one way to find it. Just remember that they are a small brewery, and have trouble keeping up with demand.
The wife and I travel, and the North Bay area is one of our favorites, so we have been able to have it many times. Worth the effort however you can get it.
Good Luck!