The following ISBN ranges have at least 500 books/other media listed in this site:

HarperCollins
0-02
0-03
HarperCollins
McGraw-Hill
Random House
Academic Press
Prentice Hall
Penguin
0-15
Oxford University Press
Addison-Wesley Professional
Allyn & Bacon
Jonathan Cape
University Of Chicago Press
Palgrave Macmillan
Columbia University Press
Focal Press
University of Illinois Press
Indiana University Press
The MIT Press
Harlequin Mills & Boon
Financial Times/ Prentice Hall
Praeger Publishers
University of Texas Press
Weidenfeld & Nicolson
Yale University Press
Da Capo Press
0-307
Zondervan
St. Martin's Press
Greenwood Press
West
Hachette Book Group USA
Ordnance Survey
0-321
Mosby
South-Western College Pub
0-330
Palgrave Macmillan
Open University Press
0-340
Ballantine Books
Abacus
0-352
Harlequin Books
Farrar, Straus and Giroux
0-375
Avon
0-385
Springer
W. W. Norton & Company
Random House
Houghton Mifflin
Penguin Putnam
Methuen Drama
Routledge
Berkley
Heinemann Library
Heinemann Educational Publishers
Scholastic
Dell
Ace
Churchill Livingstone
Elsevier Science
0-446
Grosset & Dunlap
Fawcett
Signet
Plume
Basic Books
John Wiley & Sons
John Wiley & Sons
University of Michigan Press
Dover Publications
Wadsworth Publishing
Thames & Hudson
Jove
Children's Press (CT)
0-517
University of California Press
Cambridge University Press
0-525
Wadsworth Publishing
0-552
Bantam
BBC
Faber and Faber
Gollancz
Longman
Scholastic
Bantam Press
iUniverse, Inc.
O'Reilly Media, Inc.
0-609
Houghton Mifflin Company
WileyBlackwell
WileyBlackwell
Hal Leonard Corporation
Westminster John Knox Press
Viking Books
0-671
Sams
Harvard University Press
0-679
0-684
Abingdon Press
0-688
0-689
Princeton University Press
Jane's Information Group
Frances Lincoln Publishers
Music Sales
0-7126
A & C Black Publishers Ltd
Phaidon Press Ltd
David & Charles PLC
W.H.Freeman & Co Ltd
Manchester University Press
John Murray Publishers Ltd
Saunders
Aspen Publishers
Microsoft Press
Human Kinetics Publishers
Harvest House Publishers
Arcadia Publishing
Llewellyn Publications
Random House Audio
Andrews McMeel Publishing
Rowman & Littlefield Publishers, Inc.
0-7432
0-7434
Simon & Schuster Audio
Walker Books Ltd
Polity Press
Usborne Publishing Ltd
Headline
Bloomsbury Publishing PLC
Nelson Thornes
Kogan Page Ltd
Automobile Association
Piatkus Books
Butterworth-Heinemann
The History Press Ltd
Dorling Kindersley Publishers Ltd
Time Warner Paperbacks
0-7524
Orion
Kingfisher Books Ltd
Phoenix
Ashgate
Headline
0-7566
Kensington
Motorbooks
Workman Publishing Company
Prima Games
0-7619
Running Press
0-7627
Candlewick
Jones & Bartlett Publishers
Barron's Educational Series
Bethany House
Schiffer Publishing
John Wiley & Sons
0-7653
Broadway
Peterson's
McClelland & Stewart
Mira
Institute of Electrical & Electronics Enginee
Lippincott Williams & Wilkins
Marvel Comics
Thomas Nelson
Blackstone Audiobooks
McFarland & Company
0-7867
Hyperion
Wizards of the Coast
Gale Cengage
Jossey-Bass
Routledge
Universe Publishing
0-7894
Que
State University of New York Press
National Geographic
Springer
Hal Leonard Corporation
Augsburg Fortress Publishers
0-8010
Cornell University Press
The Johns Hopkins University Press
University of Toronto Press
Grove Press
Wm. B. Eerdmans Publishing Company
University of Nebraska Press
Sage Publications, Inc
Stanford University Press
Tuttle Publishing
0-8050
B&H Publishing Group
Lawrence Erlbaum
The University of North Carolina Press
Paulist Press
Harry N. Abrams
Stackpole Books
Chronicle Books
0-8125
0-8129
Westview Press
Rutgers University Press
AMACOM
NYU Press
Facts on File
University of Minnesota Press
SPIE-International Society for Optical Engine
Zebra
Cliffs Notes
Duke University Press
Watson-Guptill
CRC
Continuum International Publishing Group
InterVarsity Press
Bentley Publishers
Tyndale House Publishers
Leisure Books
Rizzoli
CRC
Thomas Nelson
1-4000
Tantor Media
1-4012
Hyperion
Delmar Cengage Learning
Hay House
Springer
Sterling
Palgrave Macmillan
Macmillan
WileyBlackwell
Egmont Books Ltd
Dorling Kindersley Publishers Ltd
Longman
1-4129
PublishAmerica
Saunders
1-4165
1-4169
Kessinger Publishing
Kaplan Publishing
CRC
AuthorHouse
VIZ Media LLC
1st World Library - Literary Society
IndyPublish.com
Taunton
North Light Books
1-58663
Apress
VIZ Media LLC
TokyoPop
Dark Horse
TokyoPop
1st World Library - Literary Society
TokyoPop
Lonely Planet Publications
Titan Books Ltd
Osprey Publishing
Rough Guides Ltd
1-84415
Titan Books Ltd
The Crowood Press Ltd
The Crowood Press Ltd
Hachette
Seuil
Larousse
Bordas
2-06
Gallimard
Flammarion
2-09
Dunod
Presses Universitaires de France - PUF
Armand Colin
Casterman
Dargaud
L'Ecole des loisirs
Eyrolles
Fayard
Fleurus
Hatier
Robert Laffont
Albin Michel
Payot
Grasset
Dalloz-Sirey
LGF - Livre de Poche
Editions 10/18
Fleuve Noir
Pocket
Editions du Rocher
Harlequin
J'ai Lu
Marabout
Belin
La Découverte
Editions d'Organisation
Vuibert
Glénat
Ellipses Marketing
Odile Jacob
Actes Sud
2-7440
Milan
Bayard Jeunesse
Dupuis
Le Lombard
Marvel Panini France
Pika Edition
Kana
岩波書店
角川書店
学習研究社
講談社
集英社
小学館
新潮社
中央公論新社
早川書房
文藝春秋
河出書房新社
光文社
幻冬舎
ダイヤモンド社
筑摩書房
東洋経済新報社
日本経済新聞社
PHP研究所
白泉社
ソフトバンククリエイティブ
日経BP社
富士見書房
メディアワークス
Brill Academic Publishers