The November issue of Premiere magazine contains a feature on Harry Potter and the Goblet of Fire. The article titled Nobody Beats the Wiz - Inside the latest Harry Potter, as the young wizard confronts He Who Must Not Be Named has some new quotes from the actors.
UPDATE: You can see the scans of the article here, thanks Shannon.
Dan on Voldemort:
Everything we have done before has been building to this confrontation with Voldemort. Everyone felt a responsibility to get it absolutely right, to make it fantastic and terrifying, so as to not to let everyone down.
Dan on Miranda Richardson's Rita:
She's got this photographer with her all the time and everybody off-camera was in hysterics because she'd be writing with a massive quill, and every time she'd end with a flourish she hit the photographer in the face, over and over. It's little details like that that make it incredibly funny.