Tourists don't do China Town alone.
The reason China Town in Yokohama is big is because back in the days, when man's main long distance transportation means were ships, the Port of Yokohama was the most international thing you can see in Japan. This is where all the Chinese came in hope to find a new life in Japan. Hense China Town is surrounded by many touristical spots that originate from that era.
For example, instead of heading straight to China Town, you can go directly to the Yamate hill area where you can enjoy old European colonial style mansions and a view from the Yokohama Foreign General Cemetery. Then you can enjoy a stroll down to Motomachi shopping street.
After enjoying your window shopping, buying a couple of souveniors, you can stroll down to China Town for lunch and enjoy the great atmosphere.
Once you're full, walk toward Yamashita Park at the port. Be sure to stop at the New Grand Hotel across the street from the park and visit its old-fashioned lobby upstairs.
From Yamashita Park, you can either enjoy a boat ride or a red tourist bus to the MM21 district, or you can also walk along the pedestrian path along the sea.
At MM21, you can go up the tallest building in Japan, the Landmark Tower. The sunset in MM21 district often gives you a beautiful sillouette of Mt. Fuji behind Landmark Tower.
Instead of walking so much, you can also rent a Hamachari bicycle at one of the several stations scattered all over this area. These bicycles were stranded or illegal parked bikes and are well maintained. They cost 800 yen per day, requiring a deposit of 1500 upon renting. You can give back your bike at any other Hamachari station.
http://niceyokohama.web.infoseek.co.jp/station.htmlYou can do this tour of Yokohama in one day and go back to tokyo using a commuter train. For more details, ask at a tourist information counter located inside Yokohama Station or in front of Sakuragicho Station.