I've no idea where we could find something like plans for steppe villages, but if you'd like to try some of those as being simpler at first, the regular houses might be replaced by things like the yurts I mentioned. I would recommend taking a look at this absolutely amazing photo gallery here: http://www.reportages-pictures.com/Mongolia.htm
Some galleries in it are better than others, but many are superb and they can give you some ideas. I'll get our steppe guys to post any ideas they might have here for you.