Guerneville has no city hall. It is unincorporated, so there is no municipal recreation department, no city beginner class and nobody to call about a booking. The courts belong to a small special district that has looked after the river communities since the 1940s, and its published rules for the whole park system run to about one sentence.
That light touch is honest rather than sinister, but it does set expectations. There is no ladder, no roster, no published open play and no local club with a page of its own that I could confirm. If you want a game with strangers you will end up driving east. If you want an hour of coaching on a quiet court under trees, this is one of the pleasanter places in the county to have it.
The compensation is distance. Guerneville is a short run west of Santa Rosa, so the price on the lessons page is what you book at, and it is the one outlying town on this site where a short-notice hour is realistic rather than a favor.