The MLS, Loopnet, and Costar serve their purpose, however, they are all passive forms of marketing. You need to be proactive.
An easy thing to do is to go on Google Maps, type in the town where the hotel is and then type in "hotels", and it will pull up all hotels in the area - and voila! - you now have a lead list of targets. Then pick up the phone, call each hotel tell them who you are and that you have a hotel for sale, and that you would like to speak with the general manager and/or ask how to get in touch with the hotel franchisee. Once you exhaust this list, go to the neighboring towns and work out from there.
Also, you can call the corporate offices for each hotel and ask for the franchisee's information in the region.
It's good to work both angles (top-to-bottom and bottom-to-top) at the same time.