Small bar, tastefully done up in wood, with a very good range of single malt whiskies and a good selection of Japanese stuff, mainly from the Ichiro`s Malts range. Like most of these bars, it is not cheap. We spent 7,000 yen for two people`s entrance fee plus four single malts and a small plate of jerky. The atmosphere is friendly and connoisseury. If you are not comfortable with connoisseurish whisky swilling and sniffing in a tight space, this may not be the place for you. If you are, I recommend sitting at the bar if that is possible because they will put all the whiskies in the area you are interested in out on the bar and it is much easier to order. Did not really test how much English was spoken but I am sure non Japanese speakers could get by.
Open 6pm - 3am
500 yen door charge
Seats 18 people (at a stretch)
Cards:VISA, Mastercard, DinersClub, AmericanExpress, JCB
3rd floor of the Dai-ichi Houtoku building.
Quite hard to find. Take this map with you. Go out of Shinjuku JR station's Nishi (West Exit). First, find the Odakyu Halc building, which is immediately opposite the bus station on the main concourse outside the station. The Argyll is immediately to the North of here (ie. to your right, if you have your back to the station). If you find the Star Hotel (the "H" in a black circle on the map), you have gone too far. It is in the little streets in the block between Odakyu Halc and the Star Hotel.
Update: I had another chance to work out directions to this bar when I went to the nearby bar Zoetrope. This was my best shot: Print out Nonjatta's google map for this bar's locality. Go to Shinjuku station. Go out of either the east or west exits or Shinjuku station (the east is slightly easier) and walk north, with the tracks either to your immediate left or immediate right until you get to the big underpass under the tracks. There should be a stream of people passing under the tracks to go and get their rocks off in Kabukicho. I have marked it with a red cross on the map. If you are to the the east of the tracks, go under the underpass. If west, stay where you are. You should be able to find it using Nonjatta's google map from there.
3rd Floor, Daiichi Houtoku Building
Address in Japanese characters
東京都新宿区西新宿１丁目４−１７ (Can't see it?)
Japanese guide entry including map.