The NY Daily News has this article with tips about how to pick up a bartender.
It's an uphill battle, as illustrated by bartender anecdotes like this one:
"Customers think they can abuse you and say anything they want," she says. "They think, 'Ooh, she's nice to me, she must like me and want to have my babies.' They expect you to take their number. Sometimes I just tell them I'm a lesbian to make them back off."
She pauses. "But then, of course, that turns them on, too."
Still want to take the plunge?
Tread lightly, and avoid all cheesy references to red-headed sluts.