Park: The cabins in Huangshi National Park are very popular, because there are few resources, so it is generally impossible to book them, not because of the good environment in the park. You can make your own reservation in official website. If you can't book it, you can bring a small group. Travel agencies usually book rooms, and the quality of small groups is also high. I reported this to my parents for your reference http:sina.lt/f8Df.
Outside the park: If you are outside the park, you will usually stay in West Yellowstone or South Gate. There are many accommodations here, and it is also a chain hotel. However, it is better to book early than late, and it is more difficult to book in the peak season, otherwise you will live far away.
The most important thing is to have a good time: Yellowstone Weekly is mostly characteristic accommodation, not star-rated luxury accommodation, and can't have very high expectations for accommodation.