Kane Books Details
Scholarly and antiquarian books.
http://www.kanebooks.com/

Kay's Secondhand Books & Used Sheet Music Details
Used non-fiction books and sheet music, listed in categories.
http://www.kaysmusic.com/

Kazoo Books Details
Used books including hard cover and paperback, featuring more recent titles rather than old and rare.
http://www.kazoobooks.com/

Keeble Antiques Details
Rare, antiquarian and out of print books, publishers end of line titles, deltiology, old photographs and antique maps. based in Dorset, UK.
http://www.keebleantbks.co.uk/

Kelmscott Bookshop Details
Collectible, out-of-print, and scholarly books as well as search, book binding and restoration services.
http://www.kelmscottbookshop.com/

Ken Lopez - Bookseller Details
Out-of-print and rare books, specializing in modern literary first editions.
http://www.lopezbooks.com/

Ken Sanders Rare Books Details
Specialities include Edward Abbey, Wallace Stegner, B. Traven, Utah and the Mormons, and Modern First editions.
http://www.ksb.com/

Ken Spelman Rare Books Details
Fine, rare, antiquarian, academic and out-of-print books. UK based, ships worldwide.
http://www.kenspelman.com/

Keogh's Books Details
Secondhand and antiquarian books. Search by author, title or keyword. Many out of print editions, specialising in arts and literature.
http://www.keoghsbooks.com

Kloof Details
Scholarly books from all times on the law, economics, history, philosophy and other sciences.
http://www.dekloof.com/

Kolumb Internet Bookstore Details
Used, rare, antiquarian and out-of-print books (including first editions) specialialties include the former USSR, Oriental languages, as well as art, ballet and illustrated books.
http://www.kolumb.com/

Krueger Books Details
Offers Rare, signed and first edition.
http://www.kruegerbooks.com/