Pages Past  
   Collection of old, used, and rare books listed by subject.
   http://www.pagespast.com/

Powell's Books  
   New, used, and out of print books; many categories with detailed descriptions and illustration of selected books.
   http://www.powells.com/

Philadelphia Rare Books and Manuscripts  
   Early Printed Books, Substantive Manuscripts, U.S. and Latin Americana, Hispanica, Histories and the History of Ideas, Travels, Law, Religion, and Bibles (all prior to 1820).
   http://www.prbm.com/

Palette and Print  
   Offering vintage, used and rare books.
   http://www.paletteandprint.net/index2.html

Paperbacks Unlimited  
   General used bookstore, most in paperback, some hardcover. Partial inventory online.
   http://home.golden.net/~paperbacks/

Pellbooks  
   Hard-to-find books with an emphasis on German and Austrian literature. Over 6000 titles in 35 different catalogs.
   http://www.pellbooks.com/

Peter Harrington  
   Travel and voyages, natural history, children's books, fine bindings. Based in London UK.
   http://www.peter-harrington-books.com/

Plaza Books  
   First editions, literature, history, Western Americana, wine and food books, and general stock.
   http://www.plazabooks.com/

Published Page  
   Searchable used and rare bookstore, also offers book locater service for titles not in stock.
   http://www.publishedpage.com/

The Philadelphia Print Shop  
   Atlases, geographies, Americana, color plate books, illustrated travels, gift books, histories, and other rare books from the sixteenth through the nineteenth century.
   http://www.philaprintshop.com/rarebook.html

Phantom Books  
   Used, rare and out of print books with an emphasis on the unusual.
   http://www.phantoms.com/~phantom/

Pioneer Books  
   Antiquarian and secondhand books including modern first editions, children's, ephemera, Victoriana, Australiana, sports, music, maritime, military, art and Asia.
   http://www.pioneerbooks.com.au/

Pecan Tree Books  
   Rare and antique books; childrens books, first editions, signed and out of print books.
   http://www.pecantreebooks.com/

Papyri Books  
   Used and out-of-print books. Based in the Berkshires, Mass.
   http://www.papyribooks.com/

Papermill Books  
   We specialize in quality used and hard-to-find books, primarily non-fiction for adults and children.
   http://www.papermillbooks.com/

Pageant Book and Print Shop  
   Used and rare books.
   http://www.pageantbooks.com/

Princeton Antiques Bookservice  
   Literary procurement and research specialists for rare, antique and out of print books.
   http://www.princetonantiques.com/

Payson Hall Books  
   Out-of-print, rare and antiquarian books; strengths in the books about Ireland and the Irish, America (especially New England), Architecture and Art.
   http://www.oldbooks.com/

Peter Grosell Antiquarian Bookseller  
   Old and rare books. Site in English and Danish; many books listed only in Danish.
   http://www.grosell.dk/

Paperbacks.com  
   High quality used paperbacks. Listed in categories, order by email.
   http://www.paperbacks.com/

Pinacle Books  
   Antique books for sale, sorted by category.
   http://www.pinaclebooks.com/

Pistil Books  
   Offering various categories of used and out-of-print books, blank books, and journals. Also offers book searches.
   http://pistilbooks.net/

Paladin Books  
   Used, out-of-print books and magazines; hard to find titles including men's magazines.
   http://timsbookexchange.com/

Puppet Press  
   Original eBooks, rare and used books.
   http://www.puppetpress.com/

Patty's at Paddington  
   Secondhand books and Textbooks, including science, English, maths, self help, and novels.
   http://homepage.powerup.com.au/~pattpadd/

Pat Sheldon Books  
   Database of out of print books. Book searches. Worldwide shipping.
   http://tomfolio.com/shop/PatSheldonBooks/

Peter J. Hadley Bookseller  
   Rare and academic books, catalogued by subject and author.
   http://www.hadley.co.uk/

Paperback Pavilion  
   Used paperback and hardcover books; browsable and searchable inventory. Plays music.
   http://www.paperbackpavilion.com/

Purple Cactus Bookshop  
   A second hand bookshop making purchasing second hand books via the web available to customers all over the world.
   http://www.purplecactusbookshop.com.au/

Porter's Bookstore  
   Used, rare and out-of print books.
   http://www.portersbookstore.com/

Punkhorn Books  
   Hard to find, rare first editions, and antiquarian books, including biography, regional history, nature, and literature.
   http://www.bizhelper.net/Merchant2/merchant.mv?Screen=SFNT&Store_Code=punkhorn

Peterborough Books  
   Secondhand, used and out of print books and ephemera, including maps and guides.
   http://homepage.ntlworld.com/david.gray50/public_html/

P. Scott Brown, Bookseller  
   Bookstore with general and specialist lists.
   http://www.downtownbrown.com/

Pacific Rim Used Books  
   A variety of subjects, including books about Pacific Rim nations.
   http://homepage.fidalgo.net/~glend/