I can help you maybe just because I speak and read japanese but beside this ..to get tickets for japan is a tough thing especially that now they have shrinked the usual 4 shows into 2 dome in tokyo ...
when I was living in japan I was NEVER able to go to a concert because back then the way to get tickets was ONLY the phone with a bank account in japan etc and the phone was busy all day ..to be able to attend a show in japan is part of being lucky depending of the artists you follow you have to win lottery to be able to BUY tickets (only lottery winneers can purchase tickets)