My first fandom was technically Star Trek:TOS—my parents got me started when I was five. I fangirled Wonder Woman in the 70s, Beauty and the Beast & Quantum Leap in the 80s, but I never realized there were others of my kind out there.
That changed in 1996 with the FORKNI-L mailing list, where I boggled at not being alone, wrote tons of fic, went to cons, (met my future wife,) and gained my first fannish name. Within a month FK "War" 3 was starting and the Mercenaries Guild was being created; I jumped in with both feet. (I was also so panicked about posting my very first fanfic that I posted very quietly the night before the War started and used a pseudonym: "Dianne La Mercenaire"...'cuz everything sounds cooler in French.)
So I ended up Dianne La Mercenaire, and diannelamerc, and finally just "lamerc" because I was lazy (also, I was a merc from L.A., so it worked, right?).
Then when I eventually got into vidding—lo these many years ago—vidders got together in groups and distributed vids on things called VHS tapes [go ask your mother]. So a bunch of us already calling ourselves The Horsechicks of the Apocalypse (a long story involving Methos fangirls and sleep deprivation) started vidding as Apocalypse West.
The sleep deprivation continued and we all ended up using combinations of real, fannish, nick, totem, and Horsechick names (and symbols) in our credits. Honestly, it's a bit of a mess. But anything labeled "Dianne", "Dee", "Death", "The Waterbuffalo", and/or "}:o" (tilt left; it's horns, eyes, and a nose) can be laid at my door. Thus I've put all my vids (the new ones; someday I'll get the 25+some old ones up too) under "Death of Apocalypse West".
When a miracle occurs and I get an extra week or two of free time in my life, I'm gonna put all my old Forever Knight and Due South and Buffy and Angel fic up too. In the meantime, however, I've discovered fannish art and crafting and...ooooh... shinies....