From my experience of visiting Deadwood - everyone was playing a part - so the producers did not really have to look too far.

When we arrived (very tired) at our hotel and before we could freshen-up - we had to watch a show laid on for us in the lobby where a large local lady dressed-up as Calamity Jane abused her poor partner with a 'bullwhip'. The whole place was a bit like a walk through a film set.