Who is the most famous karate person?

There are 9 different major organizations in the Uechi Ryu style. The primary one is probably the Uechi-Ryu Karate-Do Association - the Soke Shubukan - and the head of the group is Kanmei Uechi.

IUKF headed by Sensei George Mattson is the largest and perhaps the best Uechi-Ryu organiztion in the US. There are few other Uechi-Ryu organizations in the US, but they are very small.