If you are just collecting chips you can hit all of the Deadwood casinos in a day. Most of the casinos are within a mile of each other. When we were there a few years ago we stayed well away from Deadwood since the hotels were very pricey. You are going to be diving all over anyway so location is not as important unless you want to gamble at night. Best thing to do is find a hotel you like and check its reviews on Trip Advisor.com. The reviews are normally pretty accurate.