We've created this Forum Thread with some workarounds and advice to assist you in publishing you ebook.
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I want to publish a hardcover, full colour illustrated story for children but notice that I can't get an ISBN from Lulu. Can I supply my own ISBN and if so, will it be printed on the back cover to sell through the Lulu store? I won't be selling through Lulu otherwise. My own private copy is fantastic, colour pages excellent, the cover excellent, it's disappointing that I may have to go elsewhere to sell it.