There are 5 Tourist Information Center run by the JNTO in Japan, one in Tokyo, two in Narita Airport, one in Kyoto, one in Kansai International Airport. The first one is the largest and most instructive and is located at the B1F in the Tokyo International Forum, next to Yurakuchō station. Tel: 03-3201-3331. Open Mon-Fri 9am-5pm, Sat 9am-12noon, closed on Sunday and national holidays.
Other useful sites
Counselling Information for Foreigners
Official site of the city of Yokohama. Includes Yokohama Echo and Yokohama Living Guide in 6 languages.