It's probably a rally hosted by one of the FMCA chapters or "areas", not the FMCA national organization itself.
I found it on the FMCA Area rally page, the South Central Area Rally. http://www.fmca.com/chapters/area-rallies.html
There would normally be more rally info on the South Central Area's own website, http://www.sca-fmca.com/
but it looks like they are in the midst of revamping it and don't have much there.
For $125 you probably got the parking site and three breakfasts, plus general admission to the seminars and some evening entertainment. I don't see that particular price listed on the registration form, though.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL