Jack Millar  
   Collectable books, sorted by category.
   http://books2000.future.easyspace.com/

Jeffrey Thomas  
   Americana, literature, fine printing, travel, illustrated books, and good books on all subjects.
   http://www.jeffreythomas.com/

Jarndyce Nineteenth Century Booksellers  
   18th and 19th Century English Literature, Social, Economic and Political History, Dickens first editions and Dickensiana. Based in London UK.
   http://www.jarndyce.co.uk/

Janey's Used Romance Book Sale  
   Historical, contemporarys, series, and paranormal romances. Prices are in U.K pounds and U.S. dollars
   http://dspace.dial.pipex.com/town/park/ed54/

JB Books  
   Offers searchable database of new, used, and collectible antiquarian books.
   http://www.jbbooks.com/

Joseph J. Felcone  
   Rare books and New Jerseyana.
   http://www.felcone.com/

John Gach Books  
   Used books in Neuroscience, Philosophy, Psychiatry, Psychoanalysis, Psychology and Social Thought.
   http://www.gach.com/

Jeremy Norman And Company  
   Used books from th 15th to the 20th century.
   http://www.historyofmedicine.com/

John Drury Rare Books  
   Fine and rare books from 1600 to 1900 particularly in the humanities: including economics, education, law, philosophy and social history.
   http://www.johndrury.co.uk/

Just Read It  
   Used books exchanged and sold; stock changes daily. Rare and interesting books always in stock.
   http://www.users.bigpond.com/themillars/

Jonathan Sheppard Books  
   Genealogical and antiquarian resource for out-of-print books and map reprints.
   http://www.jonathansheppardbooks.com/

Joslin Hall Rare Books  
   Curious, Unusual and Interesting Books of the 16th-20th Centuries.
   http://www.joslinhall.com/

James S. Jaffe Rare Books  
   Specializing in rare books, literary first editions, private press books, illustrated books and poetry.
   http://www.literaryfirsts.com/

James H. Freiberg, Books  
   Large selection of out of print, used, rare and antiquarian books in stock covering many fields and interests. Fiction, Non Fiction, History, Childrens, and Cooking.
   http://www.freibergbooks.com/

John Dinsmore and Associates  
   Used and rare books; including first editions.
   http://www.autobahn.mb.ca/~parker/jda/

John Townsend  
   Second-hand books for sale on family history, British topography, antiquarian heraldry books, plus free specialist out-of-print book search.
   http://www.johntownsend.demon.co.uk/

James and Devon Gray Booksellers  
   Antiquarian bookdealer specializing in books printed before 1700.
   http://www.graybooksellers.com/

Jacono Muntean  
   Antiquarian bookshop based in Vienna. Purchase and sale of works of literature and literary criticism.
   http://www.jaconobooks.com

Julian's Books  
   Specializing in rare and hard to find out of print books; first editions, signed/autographed books, limited editions, leatherbound books and sets.
   http://www.juliansbooks.com/