For the best Japanese groceries in Madison, go here! I have never bought something here that I did not like, and although it is a little more expensive here than at other Asian grocery stores, you get very good quality products. Be aware that they do not sell very much produce - the most I have seen in the way of produce is a small amount of seasonal fruit. However, it is the one place in Madison that I have found rice of the caliber I ate during my days as a foreign exchange student living with a Japanese host family. They are also the only place I know that sells sushi/sashimi grade fish (it is delivered every other Saturday), and they have an awesome selection of Japanese candy. The place is run by a Japanese family and they are pleasant and helpful. It's a great store any way you look at it.