Pat Kirtley, besides being a damned fine guitarist, plays more than a few tunes in this tuning: DADGAD. Not quite open D, but.... He does play in open D as well. Some of the songs on his CDs tell you what tuning he uses... also if you follow the "For Guitarists Only" link, there are links to articles of interest to guitarists. Check out the one on "Alternate Tunings Workshop." At the end he lists a whole bunch of artists and the tunings they use. You might check out the ones who play in open D, check out their CDs and find a song or two of theirs you might want to learn off them.