Hi there. We visited Hokkaido (Japan's North Island) for the weekends. Right after school, we headed to Haneda Airport. A lot of people prefer Haneda to Narita as it's much closer to Tokyo Central area. It doesn't take much time to go to Haneda if you live in Yokohama/Shonan area. But you don't wannta take trains during the heavy rush-hour, though.
This is my favorite bakery, Paul. Not only in Paris, they also have shops at Tokyo station, Shinagawa station and at Haneda airport!!
There're a lot of shop at Haneda, mostly gourmet shops. You don't need to shop around before departing from Tokyo. Simply go to Haneda to buy famouse Tokyo sweets!!