At the Hachiko exit of Shibuya station, you'll see big Hachiko crossing (with the big Tsutaya and Starbucks). Take the left street towards 109. 109 is in the centre of a Y-intersection, take the right street (Bunkamura-dori) and walk until you get to Bunkamura. Follow the street as it goes to the left of Bunkamura and take the 2nd street on the left (with Shibuya Hotel En on the corner). Go up the hill and pass Club Asia on your right, and O-East is just ahead on the left.