Kinokuniya is only good for stuff in moon and artbooks. I never buy anything English in there unless I absolutely can't find it anywhere.
I usually buy my shit from Borders (motherfucking coupons, bitches) or go to a secondhand bookstore and get mango 75% off (and no, I'm not telling, you fuckers. I need no competition).
Recently, I sold off like 75 volumes of manga. I don't regret it. Now my collect is like around 300 volumes of manga now.