Cardinal Books - Used books, including collectibles and other hard to find titles. - http://romancenovelsandseriesbooks.com/
Cat's Cradle Booksellers - Used, rare and collectible fiction and children's classics, plus biographies, science and law. Based in Illinois. - http://www.tomfolio.com/mall/catscradle/
Commonwealth Books - Emphasis on the arts, architecture, history, literature, and religion. - http://mysite.verizon.net/vze6y8ue/
Chris Hartmann, Bookseller - Sells out-of-print and scarce, primarily non-fiction, books by mail order only. - http://hartmannbooks.com/
Cliperdown Books - Scarce and out-of-print books on early Mountaineering and Angling, as well as Vintage Detective and Victorian Boys Books. - http://www.clipperdownbooks.co.uk/
Carolyn's Cookbooks - Sells used cooking and craft books. - http://www.carolynscookbooks.com/CGC/
Cambridge Book and Print Gallery - Specialises in nineteenth and twentieth century works on paper: modern original prints, fine drawings and watercolours, as well as rare books and hard-to-find exhibition catalogues. - http://www.slybrownfox.com/
Carmichael Alonso Books - Specialist in 20th century Spanish literature, women's books, art, and music. - http://www.carmichaelalonso.com/english/
Cozy Corner Books - Used, rare, and out of print books with a searchable database including both hardbacks and paperbacks plus online ordering. - http://www.cozycornerbooks.com/
Capricorn Books - Specializing in rare and used books; a general stock with larger catalogues being Military History, Science Fiction/Fantasy, Children's, Art, Antiques, and History. - http://www.capricornbooks.ca/
Camberwell Books & Collectibles - General stock of books arranged in a wide selection of subjects; accepts want lists. - http://members.ozemail.com.au/~cambooks/
Clover Hill Books - Specializes in 20th century British and American literature, poetry, literary criticism, and biography about 20th century writers. - http://www.cloverhillbooks.com/
Chozen Books - First editions, used, out-of-print, and vintage novels. Offers book search services and a mailing list. - http://www.chozenbooks.com/
Carpe Libris - Antiquarian, rare, and other interesting books, including private press, letterpress, and ephemera. - http://www.carpelibris.com
Cofion - Second Hand Books and Edwardian postcards in Tenby, Pembrokshire, UK; offers an approval mail-order facility. - http://www.cofion.com
Cranberry Book Barn - General stock of new, used, out-of-print and rare books. - http://www.cranberrybooks.com
CnD Previously Loved Books - Specializing in romance, mystery, science fiction and contemporary books. Site includes drawings, author links and pseudonyms. - http://www.cndbooks.com
C. North Books - Specializing in Western Americana, Native America, biography, science fiction, and art. - http://www.cnorthbooks.com
Cat's Cradle Books - An eclectic mix of used, out of print, and rare books. Based in North Carolina. - http://www.catscradlebks.net/
Christine's Book Cabin - Out of print, rare and used books including first editions, collectable books, and comics. - http://www.bookcabin.co.uk/
Crowes' Nest Books - Searchable database of used and out-of-print books in many categories. - http://www.crowes-nest.com/
Charles Agvent - Online inventory of books with major collections. - http://users.erols.com/agvent/
Curio Corner Books - Collectible, rare, and out-of-print, books, including children's, science fiction, Americana, and biographies. - http://www.curiocornerbooks.com/
The Castle Bookroom - Hard to find rare books on all subjects. - http://www.thecastlebookroom.com/
Charles Mckee Books - Specializing in science-fiction, horror, mystery, cartoon, Canadiana, and fishing. - http://www.charlesmckeebooks.com/
Coup de Foudre - Offers rare books in science, medicine, wine, and mountaineering, as well as tribal art, maps, and antiquities. - http://www.coupdefoudre.com/
Continental Books - Used and out-of-print books. Search or browse categories. - http://www.continentalbooks.com/continental.cgi
Curious Book Shop - Science fiction, mystery, children's books, Michigan history, sports memorabilia, and old magazines, including comic books and pulps. Includes searchable online inventory. - http://www.curiousbooks.com/
Canterbury Books - Offers secondhand and out of print books by mail in all categories, with an emphasis on Canadian content. - http://www.canterburybooks.com/
Concharbooks - Used books in over fifty categories, from first-edition factual books to all types of fiction. A store with a Celtic flavour, including second-hand CDs, videos and online games. - http://www.concharbooks.co.uk/
Christison Rare Books - Antiquarian and out-of-print books, especially those relating to or emanating from Africa. - http://www.antiquarian.co.za/
C. Dickens - Fine, rare and collectible books, maps, historical documents, autographs and manuscripts. - http://www.cdickens.com/
Cromwell Books - Used and rare books in most subjects. - http://www.cromwellbks.com/
Crecy Books - Subjects include mystery, action, adventure, science fiction, westerns. Based in Georgia. - http://www.crecybooks.com/
Cellar Stories Bookstore - Used, rare, and antiquarian Books: search or browse. - http://www.cellarstories.com/
Crabtree's Collection - Sells nature, juvenile, history, and a general selection of old and out-of-print books. Searchable inventory. - http://www.crabcoll.com/
The Colophon Bookshop - Specialists in antiquarian and in-print books about books and bibliography, literary first editions, first editions of mystery and detective fiction. - http://www.colophonbooks.com/
Charles B. Wood III, Antiquarian Booksellers - Includes architecture, landscape architecture and garden history, art conservation, book arts and printing history. - http://world.std.com/~cbw/1.html
Chaucer Bookshop - Specialising in first editions, children's, illustrated and antiquarian books of science, and medicine. Based in Canterbury, UK. - http://www.chaucer-bookshop.co.uk/
Caterwaul Books - Used and rare bookstore. Search, request a book search, or order online. - http://www.caterwaulbooks.com/