When I lived in Ft. Lauderdale, FL back in 1975-76, I was right in the middle of a hotbed of Trek fan activity. It was an exciting time, but for me only by proxy. Thanks to a controlling step-father, I never got to go to any of the conventions or mini-cons that I read about. (Sorry to bring that up so often, but really, those days were dominated by that kind of life and my Star Trek memories are affected by it.) The best I could do was collect the flyers and mailers they sent out, which was exciting to me anyway. I have all of them in plastic pages now, in my Star Trek scrapbook, and they bring back good memories of the time. I'll post more as time goes by!
Below is a scan of an ad from the back cover of The Monster Times for the 1974 3rd annual NY Star Trek convention.