R&D Fashion Dolls is a great international site where you can find Jenny dolls, like my Birthday Club doll. While she is no longer available, you will be able to find others (including other Club dolls, at much cheaper prices than what I paid on Ebay, I should add).
In addition, you can also find Momoko dolls, which are hard to find in the US (and can I just say how badly I would like to add Alice in Snow to my collection? And while you're there, check out how cute Lacy Modernist is! She's a pre-order), Licca, some Volks dolls, and limited edition Barbies (some of which are hard to find here). In addition, R&D is an Integrity Toys dealer, and often have interesting and hard-to-find Fashion Royalty, Dynamite Girl Susie (she's an exclusive for them), and occasionally FR Nippon as well.
I know a few collectors who have shopped from this site, and they not only have a reputation for great customer service, but the owners are fellow collectors and very friendly and knowledgeable as well. Plus, one of the owners, Rudi, who also runs a blog (check it out and follow it!) is actually one of the guest judges on Couture Challenge, also.
Photos courtesy Sekiguchi.