A ryokan is not a hotel with tatami. You arrive at a fixed hour, you change into a yukata, dinner is served at a set time in a set number of courses, and the room becomes a bedroom while you are eating it. Done well it is the single best night of a trip to Japan. Done badly it is an expensive evening of feeling like you are getting something wrong.
These five all take foreign guests regularly and will walk you through the etiquette without making it awkward. Rates are per person and include dinner and breakfast, which is how ryokan pricing works — the sticker shock is misleading until you account for two substantial meals.