Cosmolink is by far the BEST. The prices are good and they can even special order in things for you that they don't list, unless it's extremely rare or out of print. Even out of print/production DVDs they were able to get for me. You fill out a form stating what you want and they order them. In about a week they ship and charge your card. You usually get the items 3-4 days after that. They don't keep items in stock so that's why it's much cheaper. The page is: http://www.xxxdvd.co.jp/home.htm

Office21 is a very informative site. You can search for anything there and you can usually find it. The problem is that they are extremely expensive. For a 7200 yen DVD you'd probably end up paying 10,000 Yen instead. With their high prices i'm surprised they stay open. I guess if you buy a membership they reduced the price. The customer service is excellent and shipping is super fast. They can even special order you titles that nobody else will. I even had them special order me a rare VHS movie from a Japanese used goods site once! Here's the url:
http://www.office21.gr.jp/japan/catalog/index.htm

Lately i've been using used adult video stores in Japan that have online sites. Two of them ship to the USA but their webpages are in Japanese. It's hard enough to even find their english order form.

BTW, all these sites sell 100% legal retail packaged DVDs. You can find dozens of bootleg operations out there, but I won't go there..

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