I use Makeup alley for my research as well, like Jasmin. Once you've weeded out some clearly inane reviews the rest is really helpful.
Real people with real experience of what they use.
The freebies are easy to spot, usually the same thing all over the blogs like a rash.
Sometimes though I read a post, and the blogger has casually picked up everything from a recently launched makeup artist line, foundation, primer, eyeshadow palette, mascara, concealer, lip pencil, lipstick, and fuck knows what else, and this all easily cost over a £150, how, just how? And that happens all the time.