I always find Common Sense Media useful with its descriptions of anything of concern. It's a teensy bit conservative for us in terms of the age recommendations it gives, so I take a year off the age, but I love being able to see what possible issues there could be regarding violence, sex, language etc. I'll be giving DD the first Harry at 7 and drip feeding them from there smile

http://www.commonsensemedia.org/book-reviews/harry-potter-and-the-sorcerers-stone