We want to visit the Redlands but can't find details on accommodations. Any good places you can recommend will be highly appreciated.

indeed pretty difficult to find Dongchuan's "red earth" (or hongtudi) accommodations info in English! There are many small guesthouses which are more or less the same...

here's the tripadvisor list but it's pretty bad: www.tripadvisor.com/[...]
But you can find some more by searching user's posts like this one for example (phone number available): www.tripadvisor.com/[...]

Here's a baidu map search but it's all in Chinese: j.map.baidu.com/erU6H
... and Ctrip (search for 红土地): hotels.ctrip.com/[...]

Thanks a lot Philou, I'll have a look. Are there some better accommodations in a town half way or something?

There are several simple hotels in the Red Earth Area. None of these will be listed in a booking service.
A nice one is at the Yakoudi View point that has good views both in the evening and in the morning. The hotels have simple restaurants as well.
I only can give coordinates: 25-55-50 N 103-06-34 E. and a telephone number: 18987194896 / 15808764418. (There are actually three hotels here one with phone number: 0871-62728652 / 13658845990).
The place is on a small side road (Brick road) that starts next to a big group accommodation hotel. It is some 4 km north of Lujiagou (Which has several hotels as well) on the way to Lanniqing (The side road is near a small reservoir).

Do not go to Dongchuan itself. It is far away from the actual Red Earth Area.
Note that visiting the area can be cold and windy.

I just went there last week. Not much offering for accomadations that I could see. Some hotels are being built.
However it begs the question why one would want to go in the first place. I saw nothing interesting except the beautiful valley views during the drive. "Red" soils is quite overated.
I also was put off by the locals that come out of the woodwork when you stop your car by the road. They seem to believe you need to pay them 5 RMB for "parking" on the public roadway. I refuse to pay these scammers, although I noticed many people paying.

Good to know there is not much to do or see, we also wanted to go visit the "redlands"

Watching the latest news I started to understand your question. You want to visit states that voted for Trump.