If you want to write children's literature, you should join SCBWI (Society for Children's Book Writers and Illustrators). They send you all kinds of awesome newsletters and info about the world of children's publishing. You can join even if you aren't a published author.
I joined this year after a recommendation from one of my grad school professors, and have been really impressed with everything they've sent me.
They also hold two BIG conferences each year. The summer conference is in Los Angeles. The winter conference is in New York City.
Just to show you what caliber of speakers are at these conferences, here are the keynote speakers for the Summer 2011 conference: