Distinguished Revolver

what organization (and I use that term loosely) is actually managing the Distinguished Revolver matches and who can tell me where the matches are being held?

NRA

They are usually held in conjunction with State and Regional tournaments, so you would need to check with specific match directors and their match program to see if they have included it.

I have no idea where you are, but being in the east coast I start here:

http://www.njpistol.net/signup/match_cal.asp