From Shinjuku station to Koenji station is central Sobu line, about 6 minutes on weekdays. (It is a service of only local train stop on holiday.) Please feel free to visit the city of Koenji where access from city center is also good and you can enjoy unique culture different from downtown.
Shuttle bus, Narita Express (change to Chuo Sobu line at Shinjuku station), Skyliner (Yamanote line at Nippori station, transfer to Chuo Sobu line at Shinjuku station) Please use.
Shuttle bus (change to Chuo Sobu line at Shinjuku station), Tokyo monorail (change to Yamanote line at Hamamatsucho station, Chuo Sobu line at Shinjuku station), Keikyu line (Yamanote line at Shinagawa station, Chuo Sobu line at Shinjuku station Please transfer).