I wouldn't worry about sales from 2003 and 2004 as the book hadn't been published then. Perhaps you were finding out the wrong information.
Since the book has an ISBN number it is likely in some libraries and so there have been sales
Why don't you ask the author David Carroll about it. They put the effort in and so they should get the rewards or lack thereof accordingly
There are plenty of bookshops in London. I'm sure one of them would have a copy or two.
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It is not looking good. Royalty statements for December 2003 and for June 2004 state 0 sales. I am hoping that two miscommunications with the publisher who have asked for information about what platforms I frequent will now enable us to turn up the heat and get some sales. I am also hoping that people will have taken the book out of my local library, and at least read the rear cover of it at the Christian Literature Crusade bookshop here in London, UK.
I am not bothered at having 0 sales in the two years that I have been advertising it with varied text on X, formerly Twitter, and here at the Film Boards. I might take it direct to the public at Christian events, and at some churches. And I might also write a stage performance for the martial arts, yoga, and meditation to be demonstrated, where interested people can order the book. And again I might buy some books from the publisher and sell them direct to the public out of a van.
I remain hopeful.
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I'm waiting for the follow up book: Idolatry: What it might be
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Bump for those who have not seen it.
I like making slideshow movies, see
https://littlebits3.com