Anime conventions are hit or miss. Never hook up with a chick at one, you'll end up with one of two kinds. 1. Really desprate and clingy, or 2. psycho. No joke, but on rare occassions you could stumble into a good convo with a chick and something will come from it. Gotta be REALLY careful though. Also, steer clear of those ones that seem to flaunt their stuff.... I've noticed most are only after nerds wallets.
Comic stores, music cafes, parks, everywhere. Its just do you notice that they are cool and nerdy girls.