I need an ISBN
An International Standard Book Number (ISBN) identifies a specific book. On printed books, a barcode is a graphical representation of your book’s ISBN. And in the publishing industry, an ISBN is the most widely used format for identifying your book. This number is used for such as cataloging your book in libraries, stocking and distributing your book in bookstores, and ordering the book online. A separate ISBN is required for each format of the book, e.g., paperback, hard cover, eBook (EPUB, MOBI), PDF book, etc. After all if one of your readers wanted a paperback copy, they would want to be able to find that specific format.
A new ISBN is also required for each different edition of your book. Now, if after you print your book or distribute it as a eBook you notice a few spelling or punctuation errors, you can correct these in next reprint or redistribute the eBook using the same ISBN – as long as the content is not changed. If you are changing content, adding, deleting or revising text, then it really is an updated version, a different book, so you need a new ISBN. If you’ve updated your book, you want your audience to find the new edition … registered under the new ISBN.
If you are a Canadian Publisher, or Indie author self-publishing your book, then you will start by setting up an ISBN Canada Account with Library and Archives Canada, so that you can assign an ISBN for your book and adjust information about your publication. The International Standard Book Number (ISBN) Canada online system is a free service. It allows you to manage your ISBN account and logbook (record of all your ISBNs). You can also order a CIP (Cataloging in Publication), which is used by libraries to organize their book collection. Library and Archives Canada requires publishers to complete a Legal Deposit for each book format published but you can read more on that here.
If you are looking for the ISBN Agency in your jurisdiction visit the International ISBN Agency. (There may be a cost associated with the purchase of ISBNs from some agencies.)
INTERESTING FACT ~ ISBNs were 10 digits in length up to the end of December 2006, but since 1 January 2007 they consist of 13 digits. ISBNs are calculated using a specific mathematical formula and include a check digit to validate the number.