where can i get the same dogtag as justin bieber?

I HAVE NO IDEA

it was given to him by a fan who's relative died in the war, so you can't. :/

you can't. U can get a dog tag like his, but not with the same writing. Becuz u had to be in the military and had to had that person's same info.
So if you want to be like him, try to get a dog tag, just with different writing.