Calm down, honey, didn't recognize it.
There are several ways to get a hand on tickets.
Buying them online through a middleman service, winning some on a japanese auction also with a middleman service or even buying some being there (mostly there are tickets at reseller stores still some days before a concert).
But if you want them before, you need a middleman service. At least I don't know other ways, I never bought tickets.
Maybe you should take a look at immel's guide to get to a Ayu concert:
http://www.ahsforum.com/forum/showthread.php?t=70001