Ok, how you get concert tickets: (many of these have already been mentioned here)
1. The official way - Just forget it, it ain't gonna happen if you aren't living in Japan and you likely will not be able to get the very best seats because they all go to fan club members and foreigners can not join the fanclub. So just resign yourself to that. :)
2. Yahoo!Auctions - However sellers will only ship to Japan so you need to either be living in Japan or get someone in Japan to bid on the auctions for you and then send the tickets to you - you might have to pay this person to do so as well as pay for shipping costs.
3.
Akibado is a website that offers to bid on Japanese auctions for foreigners, but their prices to do look pretty high to me and I haven't used them before. However you might want to give them a try if you can't find anyone else to bid on the auctions for you and the Harajuku option listed below isn't possible for you either.
4.
THE BEST way to get tickets is to not get them until you are actually in Japan. It sounds very risky, I know. If you are flying to Japan and getting a hotel room and spending all that money just to see Ayu live, you would generally like to have the tickets first so that you know for sure you are going. But trust me that this way is the easiest, least confusing, and ultimately cheapest way to go.
If your concert is in Tokyo or the surrounding area (Yokohama, Saitama, Chiba, Tochigi etc) what you want to do is go to a ticket reseller shop in Harajuku. It's very easy to find since it is on the famous Takashita Dori st.(famous for its crepes, fasion, and idol shops.) On the Tokyo Metro system, take the green Chiyoda line to the Meiji-Jingumae stop. Exit the station and you should see a big store across the street called Snoopy Town.(this is a cool place to check out since it has more Snoopy merchandise than anywhere in the US.^_^) Cross the street to Snoopy Town and then continue down the sidewalk to the left. Soon you will see Takashita Dori on the right. (You really can't miss it, there is a big archway over the start of the street that says Takashita Dori) It's a narrow crowded street filled with Idol shops that sell every photo, key chain, pen etc with Ayumi, Gackt, MM, L'arc and zillions of boy bands on them - Don't spend all of your money before you get to the Ayumi tickets! lol. About 3/4s of the way down the street there will be a lingerie store called LOVX on your left.(don't confuse it with the LOVX building that will be on your right about 1/2 way down the street. That store just sells cosmetics.) There are a set of stairs in front that lead up to the second level of the LOVX building and inside of there is concert ticket mecca. They have tickets for sale for every major concert tour currently going on as well as sell tour goods from past tours, all in glass displays, so you can easily pick out what you want. Best of all, the prices are reasonable. I actually paid less at that shop for Ayu tickets than I did through Yahoo!Auctions and the seats were comprable. Also, as the concert gets closer they will seriously mark down tickets that haven't sold yet. I saw one 400 level ticket that they had for the Saitama show which hadn't sold yet(the concert was the next day) and they were selling it for 3000 yen! Pretty amazing considering that the ticket originally cost 7,800. They have tickets for all over Japan, but obviously the area they are the most well stocked for is the Tokyo area.
Much Japanese isn't required to buy the tickets. You can simply point to the one you want and they'll get what you mean. Of course speaking at least some Japanese is helpful, but you should be able to get by mainly on gestures and their limited English ability. :)
So if you want to go to a concert in or around Tokyo all you need to be thinking about is that shop in Harajuku. :) It's easily the best option.
5. The last option are scalpers. Your likely to pay more, but usually they are better seats. For example, I had 2 tickets for the Sun. Saitama performance - both were for the 400 level(far back from the stage). So I found a scalper and traded my 2 400 level tickets for 1 200 level ticket + I had to pay 3000 yen. You generally don't have to try and spot the scalpers. If your concert is one of the main ones(like Saitama, Yoyogi, Osaka) they will be waiting to pounce on you just as you leave the train station. Authorities must not care about scalpers because they do it wide out in the open and very obviously. It's worth noting though that I didn't see any scalpers at the Hiroshima show last year. However, they were all over the Saitama show this year. For this option it's good to at least know how to count in Japanese and know what 'man' and 'sen' yen mean, that way you can bargain with them. As I found out, this is also an excellent option if you already have your tickets but want a better seat.
I wish. :) The tickets to start with cost 7,800 yen which is roughly $80. But expect to pay at a very minimum 10,000 yen. But it more than likely will end up being between 12,000 and 17,000 yen. ($120-$170) And that is just for bad to mid range seats, not the best seats.
