What outfit for Billie joe Armstrong?

Alright, it's not that hard of an outfit.

First, you need the proper hair. Normally, Billie Joe's iconic hair is the medium/short length hair that's black and layered. Mess it up with pomade or hairspray, gel, wax, etc. Be sure to have it cut properly by a stylist before anything. Bring in a few pictures of him and they'll know how to cut it.

Next, you need the right clothes.

Shirt:

Try shopping for a black, button down shirt that's fitted, (fitting reasonably tight but not extremely tight). To get that kind of shirt, shop at British stores, like Topman or Ben Sherman.

Tie:

It's a reasonably easy item to get; look for a quality skinny red tie.

Pants:

Billie Joe usually wears black skinny jeans, though sometimes he wears red and/or red and black vertically striped skinny jeans, and I'd turn to British stores to get a pair. Or, you could get some Levi's Skinny or Super Skinny jeans.

Belt:

A 3 pyramid studded belt. Hot Topic is your best bet for a quality belt that lasts.

Shoes:

A pair of black and white Converse (preferrably Chuck Taylors) should do. They can be either low top or hi-top, though Billie tends to wear low-tops more often, sometimes switching the white laces with black ones. Or, for a more "21st Century Breakdown" era look, go for solid black Vans or Creepers.

And finally, don't forget the eyeliner! And voilah! You're Billie Joe Armstrong (kinda). Hope that helped.