Personally I think one of the most prestigious acting schools in the world is Julliard. Some of the most gifted actors of today studied at this school. This place isn't cheap though. Tuition runs around $23,000 a year and that doesn't include room and board, but actors have a better chance of winning a part if they've had classes. Besides, Julliard offers an internship program which could help out greatly. For more information, check out the site:
www.julliard.edu