Well, if you happen to go to Michigan, there is a small store in Novi that sells J-pop CD's (including Ayu's!) and magazines
The store has all her recent ones (A COMPLETE, NEXT LEVEL, Rock 'n' Roll Circus) and a few older ones from other artists too
As for the magazines, they have all recent ones, most with Ayu on the cover, or being featured in DejiDeji
I've only been there twice, though~ Hopefully they will have more in their inventory when you come, and if you have the chance to go~!