My first inquiries into the things had me believing that I was going to have to plunk down some cash to get one. But then I saw that Smashwords, the website on which I was going to release my first self-published work, would give you a free one. They listed the variety of ISBN's that you could get and seemed to be saying that if you paid for one, that it was only a sort of vanity sort of affair and not really necessary.
Originally I had intended to first put things out there on Amazon, but Smashwords had a great guide to self-publication and was going to give me this free ISBN. So I pored through their guide, grabbed the ISBN they gave me and released my work onto the world. Then it was easy to release the same book on Amazon, with just a little change to the book's front matter, using the ISBN Smashwords had given me.
But now it seems as if that ISBN isn't a magic cure-all for what I needed. On other websites where I've gone to market my book, entering that ISBN gives you a "book not found" error. Often, you can go ahead and enter the book anyway, leaving the ISBN blank. But that leaves me wondering if I needed to get one of the paid-for ISBN's anyway if I wanted people to really be able to find my book.
Working with the Create Space website to make my book available as a print-on-demand version, it turns out that website is going to give me another free ISBN. The Smashwords guide did tell me that I didn't want to use the same ISBN for my e-book version as I was using for a print version, so that works out. But am I going to run into the same trouble trying to market the print copy of the book? Will I run into websites that don't recognize the ISBN? If so, what's the point of getting the free version?
Wikipedia tells me that issuance (their word, not mine) of ISBN's in the U.S.A. is the responsibility of a private company. R. R. Bowker. The article mentions prices ranging up to $125 for a single number. Yep, they weren't kidding. But I can get 1,000 ISBN's for $1,000! What a deal! For $250, you can get 10 ISBN's, so maybe for many first-time, self-publishing authors, that's the way to go. Get a variety of the numbers for various e-book and print versions of your book. I'm working on book #2, so am going to have go through this all again soon, so maybe having multiple ISBN's to use would be helpful. There's just the sticking point of not having $250 to drop, let along $125.
So, the mystery continues. We'll see if somewhere down the road, all these free ISBN's end up being worth what I paid for them and I end up having to switch all my books to purchased numbers.