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:

Here is an hugelkultur article he wrote:

You will find fantastic images on his website.