If you are interested in finding out more about a specific school or course, it’s normally easiest to contact the school directly – most are happy to send you their information free of charge, and will often let you visit and check out the facilities too.
If you are unhappy with the fully sanitised information provided by the schools themselves, find a graduate and talk to them. The best way to find out about the positive and negative aspects of any course is to talk to people who have done it. Most reputable schools should be happy to put you in touch with recent graduates.
Of course there are plenty of reviews and opinions available on the web too. For starters you can check out filmmaking.net’s Film Schools Database which includes comments from past and present students for many schools. The Library Of Annotated Film Schools at filmmaker.com is also worth checking out, and don’t forget that there are many discussion forums (such as the filmmaking.net’s Discussion forums) in which you can post questions.