Man if all men hit on girls like the way AT people seem to do it, then the pimps and models have no chance.... lol!!
Dude, I learn this the hard way but you HAVE to remember, as the old confucious says, "many fish in this big pond". And as I say, " if you don't like fish in this pond, drive to the next pond "
Now, keep your composure, don't give a hoot on the outcome, just go up to her (YES, ESPECIALLY if she is with ther friends) and just say, "can I please talk to you for a sec" and then ask her out for dinner. Simple as that. If she says no, and you really like her, then ask her again next time. She'll give in one of these times. No girl says NO to and ATer for ever.
Best of Luck.
Davi