“But wait a minute,” you say. “I saw a site on the internet selling really cheap ISBNs. Why can’t I buy one of those?
”You can, but I wouldn’t. While Bowker does have a very select few legitimate ‘Channel Partners’ with whom they work, such as Amazon, those fly-by-night companies you see all over the internet selling cheap ISBNs are almost certainly not affiliated with Bowker, and thus are not authorized to sell you an ISBN. So why do they do it?
Source: Where Should I Buy My ISBNs? | Celebrating Independent Authors
Look before you leap; there are a lot of scammers out there targeting aspiring writers who are trying to cut costs. Yet, those authors might actually be cutting their throats.
I’m happy to have a publisher who writes for Indies Unlimited. She does a lot of research and that saves us money. ISBNs don’t grow on trees. So, if somebody is selling them cheaply, there’s a reason and it probably ain’t good. If you’re into self-publishing or are running a small press for your books, this is a must-read article.