For me the first fandom I ever wrote for was V and the evidence is still in a drawer of my filing cabinet at home. I was no more than 12 and I thank the Lord every day that I had never heard of the internet and so no one but my sister ever saw my efforts. I also get down on my knees and thank any deity listening that the world never saw my Trek Mary Sue :).
What was you're first fandom (doesn't have to have been online)?
We you a reader or writer in your first fandom?
If you were a writer did you publish?
If you were a reader did you interact with the authors?