The Drupal conference will be held at De Brakke Grond, a nice place in the centre of Amsterdam with a Flemish (Belgian!) background, just like Drupal. "The Brakke Grond is famous for its large selection of Belgian beers, and of course for its Flemish cuisine." (source). In the afternoons there will be food available, and coffee, tea and softdrinks are available too.
Most of us will be staying at the Winston Hotel, a hip and cheap hotel in the centre of Amsterdam. If you would like to stay there, please check their website and book a room. There are still rooms available, but be sure to book one as soon as possible. In case you want to share a room with a fellow drupalcoder contact Ber / Bert.