Get to Burning Man. Now. Tons of arty goths. It's their yearly mecca.
Goth events do exist in all major cities, but they tend to be only once a month traveling clubs. Very easy to find on the internet/as facebook events. Be prepared for the music to be INSANELY LOUD. Highly recommend
http://www.amazon.com/gp/product/B0044DEESS
Out here the goth girls I've been with spend 2-3 hours getting into full regalia for that one night once a month, then would be relatively normal looking the rest of the time. "Manic Panic" and other temporary hair dyes will go in Friday night, they'll go to the big concert or club scene, then wash it out. They follow the usual rules: Teen girls are all about knowing bands and music and following their friend's opinions, once they get to 25 they're over that and more interested in you.
Absinthe from
http://www.stgeorgespirits.com/ is the top of the line. It's friggin $12 a shot (and $80 a bottle at BevMo). If you order it in a club, order it as a shot with a glass of ice on the side. When you mix absinthe and water it will louche
http://en.wikipedia.org/wiki/Louche It pretty much tastes like licorice. Ouzo will also louche and is slightly cheaper. You can also make your own at home cheap by soaking star anise in vodka for a 1-3 days (depending on taste you're going for), straining the seeds out, then add sugar to taste. There's plenty of absinthe recipes on the internet, and yes, being invited to taste your home made absinthe will work with the under 25 set.
The goth scene has a high overlap with the "Steampunk" scene as "goth lite" --lots of leather and corsets, but neo-victorian with emphasis on brown leather instead of black leather, and we guys get to dress way cooler. Easy source of outfits:
http://www.steampunkemporium.com/steam.php
Steampunk is easy to find at
http://www.abneypark.com/ concerts, as well as any DJ party playing them. You can also search through
http://www.thesteampunkempire.com/ for local cities. The night concerts at
http://makerfaire.com/ will have goth/steampunk mix. The firearts festival at
http://thecrucible.org/ had some goths from burning man in full regalia, but they were a minority.
And for some damn reason that I don't understand, goths love to show up at my local horse race track
http://www.goldengatefields.com on Weiner Dog Race Day.
http://en.wikipedia.org/wiki/Dachshund_racing You'll find them in full corsets and makeup in the middle of the afternoon, sweating in the cheap seats in full sun under black lace parasols waiting for a friend's dog to race (and do horribly --it's a weiner dog after all).
You should also check out the Amateur Burlesque scene. There's all sorts of former Suicide Girls (it was big 10 years ago) who now dress up as 1940s pin up models and then strip down to pasties on their tits. They all kinda hang around waiting for their turn to get dressed up and get their five minutes on stage. Pretty easy to chat up --they want to be distracted and calmed down before they get on stage. I find them all midgets around 5'2" so it's not much my kind of women, but they're all thin and exercise. Here's one of several traveling shows in SF. Their Monday shows are $5
http://www.hubbahubbarevue.com/