You also have to remember that since the death of Gen. Choi, the ITF has split into 3 different bodies, each claiming to be the legitimate heir to the original. Also there are some independent groups out there now who have split off from the ITF such as the United States Taekwon-Do Federation (USTF) out of Colorado (which was at one time the "official" governing body for the ITF in the USA).
One large organization of note based out of Arkansas is the American Taekwondo Association (ATA). I think they also have experienced some fractures in their organization.
Something also to take note of is how it is spelled. Taekwondo - used by Kukkiwon and ATA TKD. Taekwon-Do - used by the ITF and related TKD groups. Tae Kwon Do - used by many independent and traditional TKD clubs and organizations.
I do think this is the best TKD forum that I have come across on the Web that is not specific to either the ITF or Kukkiwon (WTF) TKD (or for that matter any other organization), and with some very knowledgeable people on board. What might be easier than compiling an endless list of governing bodies is for anyone on this forum who are not under either the Kukkiwon or ITF umbrellas, state which organization they are associated with so Patrick can at least get an idea of what organizations are represented on this forum other than the Kukkiwon or ITF.