There is a great DADGAD site: http://www.ice.el.utwente.nl/~han/dadgad. It has an extensive table of chord positions for the tuning, info on "theory", and links to other sites.There is also a book called "The Irish DADGAD Book", by Sarah McQuaid. She plays in an Celtic band and contains a lot of the info in the site above plus a number of arrangements. The arrangements tend to be a melody with the occasional bass note and I suspect they are imitations of bazouki style. It is published in Ireland and Elderly's sells it for about $15. There is a cassette that comes with it for another $8 or so.
I haven't had the time to really explore the tuning yet; but I think it sounds great wit Celtic music and I hope you get into it more efficiently than I am doing.
Murray