OnJava.com have a sample chapter from the book ‘Maven: A Developer’s Notebook’, which gives a quick headstart into getting started with Maven for your build process.
I have just started to investigate the use of Maven for one of my own projects, and I am impressed so far – in particular with the fact that the same targets that I would write again and again in Ant for different projects are now just part of Maven by default – it already knows how to compile, run JUnits, generate Javadoc etc, you just configure where your source and target directories are (if they are non-standard and not following the suggested directory layout that Maven will use by default), and it gets on and does it thing. Very cool.