Birthdays.....

My friends having a costume party, and its american themed, im thinking musician, but rock icon,but have no idea, I was thinking slash, but i dont have a hat... so then I thought billiejoe armstong, black shirt, red tie, spiked hair?
Im a girl, but I have short hair, but anyway, any ideas?

Also what should I get her? She's just turned 16, she's a fan of one direction etc....
I dunno what to buy her..... :)