The dreams section of Yahoo Answers, for one. But a much better website would be http://www.experienceproject.com/
There’re a few different sections for lucid dreaming, but here’s just the first one I found: I Am A Lucid Dreamer
Dreamviews.com is one of the best sites on lucid dreaming I’ve come across. Their forums are full of helpful advice on LD and full of people sharing their experiences.
I agree with Gus S. It’s a large community of people sharing and interpreting dreams– very quick and friendly.