They are not hard to play at all. The left hand just holds the thing steady and the bowing hand doesn't do much apart from strike the strings. The left hand strings are arranged in 2s, 3s, 2s, 3s etc and are the black notes, ie sharps and flats. The other side are the naturals or white piano notes. The technique is just to start off slowly and with practice the dexterity and building the speeed will come with time. I don't think they are used for playing fast dance music. Do you mean at sesions? You'd be looked on as a bit of a novelty I guess. They are generally used as an accompaniment to songs or sometimes to play slower tunes.
Yes, the EMS does have a web site. http://www.earlymusicshop.com/search.aspx/en-GB/?q=bowed+psaltery will show you the range they have. They range in price from just over £100 to just under £200. They do kits also which you have to make yourself but this may not be an option if you have an impairment.
Hope this is of help. Do let me know how you bet on. Mike.
m.billington90@btinternet.com