I received an email from Paul Wheaton of a permaculture workshop he did in Missoula on building a hugelkultur.
Here is a short video from the workshop. The general idea is that if you build your raised bed with a lot of wood, you should be able to go the whole summer long without irrigating or fertilizing.
His Video: http://www.youtube.com/watch?v=sp_IObIkInQ
Here is an hugelkultur article he wrote: http://www.richsoil.com/hugelkultur/
You will find fantastic images on his website.