Eric Marcotte, a Slide Rule Collector  
   A personal compilation of information on slide rules with much information on his own collection.
   http://www.sliderule.ca/

David Crate's Slide Rules  
   Assorted slide rules for sale as well as some historical information.
   http://www.amug.org/~puppy/

Slide Rule Instructions and Prices.  
   Instructions on use of slide rules, and a guide to the price of slide rules.
   http://www.sliderules.clara.net/

Slide Rule Universe  
   Extensive on line archive of slide rule information, plus a catalog of available rules.
   http://www.sphere.bc.ca/test/sruniverse.html

The International Slide Rule Group at Yahoo!  
   A community of slide rule enthusiasts. Several hundred posts a month.
   http://groups.yahoo.com/group/sliderule/

Sphere Research's Slide Rule Universe  
   Online sales and swap meet. Private individuals only.
   http://www.sphere.bc.ca/test/swap.html

House of Slide Rules  
   Large categorised collection with photos and notes.
   http://foraker.research.att.com/~davek/slide/

SlideRule Trading Group  
   Private trading for members of the group.
   http://groups.yahoo.com/group/sliderule-trade/

Dennis Farr's Slide Rule Collection  
   List of collected sliderules.
   http://geocities.com/dennisfarr/slide/

Slide Rules and Calculators  
   Images grouped by type.
   http://chris.gillings.com/collect/slide/index.html

Slide Rule Page  
   Archives of photos of large personal collection.
   http://home.att.net/~jcurrent/srule.htm

The Oughtred Society  
   Membership group dedicated to the history and collection of slide rules.
   http://www.oughtred.org/

Slide Rule Collection  
   Todd Tolhurst describes his collection, some with pictures.
   http://www.toddtolhurst.com/sliderules/index.html

Discovering Slide Rules  
   Relates a story about how one person found a giant cache of new-in-box slide rules.
   http://www.sphere.bc.ca/test/discover.html

Peter Holland's Slide Rules  
   In German and English. Items for trade with descriptions of condition.
   http://www.peterholland.de/

The Slide Rule Guy  
   Site for Jay Francis, a collector of slide rules and antique mechanical calculators. Items for sale or trade, and many related links.
   http://www.slideruleguy.com/

Mechanical Calculating Equipment  
   Collection of Wolf-G. Blümich. Berlin, since July 1998 periodically updated. Bilingual [mostly German, but some English].
   http://www.salvator.net/rechner/

Antiques of Science & Technology  
   Pictures and descriptions of a number of slide rules.
   http://northshore.shore.net/~jim/wcat26.html

Chris Osburn's Slide Rule Collection  
   Explanation of slide rule scales, FAQ about buying and selling rules, and a description of his collection.
   http://www.muppetlabs.com/~chris/sliderule/

Sphere Research's Learning about Slide Rules Site  
   Repository for information, pictures, history and links to sellers, other sites and experts, and an online store.
   http://www.sphere.bc.ca/test/2learning.html

Slide Rule Emporium  
   Pickett Slide rules forsale. New in the box and many models available from the pocket size to 4 foot teaching rules.
   http://members.aol.com/slideruleemp/

The Sphere Research Slide Rule Archives  
   Slide rule model information, pictures, and history from all over the world.
   http://www.sphere.bc.ca/test/2archives.html

Model Aircraft Performance Slide Rule Calculator  
   Custom slide rule for sale. Online calculations which cover the same functions available on the site. Manual included with the slide rule.
   http://pages.sbcglobal.net/limeybob/

Space Race Slide Rules  
   Features some slide rules used in early American and Soviet space programs.
   http://www.nasm.si.edu/galleries/gal114/SpaceRace/sec300/sec320.htm

Kung's OnLine Slide Rule Bookmarks  
   Comprehensive annotated collection of links.
   http://www.geocities.com/kungyiji/srule.htm

Ted Hume, Slide Rule Trader  
   Slide rules bought, sold and traded.
   http://members.aol.com/tedhume/page1.html

Slide Rules from German Manufacturers  
   A collection of slide rules, with descriptions and pictures. Also, some links to other slide rule sites.
   http://www.gaehrken.de/sr/index-e.html

The Slide Rules  
   A hyperlinked history of slide rules, details of the author's personal collection, and contact information.
   http://www.giovannipastore.it/index_english.htm

Otis King's Patent Calculator  
   Probably the most complete collection of Otis King's Patent Calculator (cylindrical slide rule) information on-line.
   http://www.svpal.org/~dickel/OK/OtisKing.html

The Death of the Slide Rule  
   Hyperlinked essay with citations by James Redin covering the rise of the portable calculator and the demise of its predecessor.
   http://www.dotpoint.com/xnumber/hp.htm

Chris Sangwin's Slide Rule Page (With Other Mathematical Instruments)  
   Hyperlinked essays about slide rules and related tools, and some copyrighted downloadable files for making one's own slide rules.
   http://www.mat.bham.ac.uk/C.J.Sangwin/Sliderules/sliderules.html

Slide Rules  
   Dedicated to one man's collection of slide rules (and includes a photo gallery), plus a few links for those who want to find out more about them or where to buy one.
   http://www.eyrie.org/~dvandom/slide/index.html

HP Museum - Early Calculators  
   Some non-HP calculators that were introduced anywhere from centuries ago to the late 60's.
   http://www.hpmuseum.org/prehp.htm

Napier's Bones and the Genaille-Lucas Rulers  
   Presents Napier's Bones and the Genaille Lucas rulers in ready to print forms: Postcript and PDF.
   http://www.nmt.edu/~borchers/napier/napier.html

Slide Rules in Thailand  
   Front and back mages of some slide rules for sale.
   http://www.geocities.com/ipairin/

Slide Rule Trade Offer  
   An offer to trade kite aerial photographs for slide rules.
   http://www.arch.ced.berkeley.edu/kap/background/kapoffer.html

Peter Owen, Collector of Slide Rules  
   Texts and photographs.
   http://homepages.tesco.net/physics/

IM2001 - 7th International Meeting for Slide Rule and Calculating Machine Collectors  
   Munich, Germany, September 14 - 16, 2001.
   http://www.rechenschieber.org/

Giovanni Breda's Slide Rule Collection  
   Giovanni Breda shows his collection. A sheet for each rule is provided including high resolution images. Links to other collector's site are also provided.
   http://www.sliderule.it

Mike Konshak's Slide Rules for Hairy-Eared Engineers  
   A private collection of slide rules in excess of 500 different items scanned full size and categorized by company or continent. Also offers a comprehensive glossary of slide rule terms.
   http://www.konshak.com/MK_Sliderules.htm

Technical Collectibles  
   Slide rules and planimeters for sale.
   http://www.technicalcollectibles.com/Slide%20Rules/slide_rule.htm