Where does ISBN come from?

I have been trying to publish my own book and considering blurb (see my last post) for their unique publishing service. Then I realized that Blurb does not provide you an ISBN which you would need if you would like your book to be sold in the bookstore or placed on the library shelf. However if you manager to buy the ISBN yourself, blurb book writing platform BookSmart(TM) does provide the way to embed ISBN on the cover along with barcode. So where does an individual get ISBN from? I did some research and found out that a company in New Jersey named Bowker owns the ISBN and has been the sole supplier of the 13 digit unique book number for last 3 decades since the code was adopted by ISO standard organization in 1970.
Bowker provides all the necessary information as PDF on this webpage. Getting an ISBN is not cheap though. It costs roughly $125 for a single but if you are a publisher and buy in bulk it can cost as little as $275 for 10 ISBNs.
What is the benefit? - well other than being able to sell on Amazon or other bookstore, public libraries get access to newly published books list from Bowker. Who knows, libraries might end up deciding to order your books, can make you famous and rich.
When you have ordered and received your ISBN, here is the instructions to add it to your book in the BookSmart. Long live blurb and happy publishing !