Used, Out-of-Print, and Antiquarian (Subscribe)
Links
VirtualGeula - The Antiquariat
Sells new and used Sifrei Kodesh, including many new Seforim printed in Israel not listed elsewhere. Also includes the Judaica Archival Project, which copies and preserves rare seforim and sends them to you in .pdf files
The Book Gallery
Large used book store in Jerusalem specializing in antique and used books in various languages on Judaica, Israel, and yizkor books. Ships worldwide.
Dan Wyman Books
Unusual used and out-of-print Judaica in English and other languages, including history, yizkor Books, the Holocaust, rabbinics, Yiddish, and the Jewish Labor Movement.
Broder's Rare and Used Books
Rare and used Jewish books, with free book search service.
Antique Seforim
http://www.antiqueseforim.com/
Buyer and re-seller of Hebrew books, seforim, and Jewish manuscripts, including entire library collections. Located in Borough Park, Brooklyn; will travel worldwide.
Antiquariaat Lilien
Seller of rare and out-of-print Judaica books, prints, and posters. Located in the Netherlands; apparently ships worldwide.