I went tonight, it was unbelievably amazing!!!
Line 10 Sanyuanqiao station. C1 exit
walk 100 meters to bus stop(follow pedestrians, you know where the bus stop is, if not, cross a 2-meter wide road which is a one-way down from the bridge, you can't really cross to the other side anyways) take 916 bus,2 stops,
get off at 大山桥东站 (Dashanqiao Dong Zhan)
Walk towards 望京国际商业中心(Wangjing International business center which are 8 bold letter, red at night, on top of the building facing you when you get off the bus) for 450 meters or less
***I seriously suggest take taxi from the subway station, only 12kuai, 15 when it's busy I assume. Not worth the trouble unless you really feel like taking buses.
The Japanese Ramen street should be quite noticeable once you get there.and check the tiny map on the official site to find the exact location.
If you are off the bus but don't see any bold letters, you should cross the street that you just came from to the other side, now that you've walked across the street towards the center, you should be on the left side, there's a bank branch there, the first thing you see, and keep walking, until you see an opening on the wall, a square-like space inside with a merry-go-round. Alas, the street is behind it, now you see the Japanese characters, and you are prepared to buy cards which can only be purchased 100 kuai every time...I'm sure you need to put more than 100 in, it's delicious!!!!!!
http://ribenlamian.com/chinese/index.html# is the official site. There's a tiny map there without much direction though.
Hope this is helpful if you still want to go...
Thx