I'm writing my own LaTeX book!
There are many good books to learn LaTeX, like LaTeX and Friends by Marc R. C. van Dongen (my favourite) or the LaTeX Guide from Wikibooks. But sometimes you find that they go either too deep into technical details, or they don't really scratch the surface of what LaTeX can offer.
That's why I decided a couple of weeks ago to write my own book about LaTeX.