Access Hollywood has released two clips of Tom behind-the-scenes of Harry Potter and the Half-Blood Prince. The filming took place when they were filming the Knockturn Alley scene where Tom’s character Draco is being followed by Harry, Ron, and Hermione (Dan Radcliffe, Rupert Grint, and Emma Watson respectively). Tom is interviewed in this first clip, and the second is literally just cast and crew hanging about while they wait for a take.
UPDATE: These videos are from Hulu, so if they are unviewable in your country, you can try watching them here and here.