* The name is misspelled. Double check the spelling.
* The author is less well-known. There may be an author named James Coltrane who has published in a specific genre or niche, and hasn't achieved widespread recognition.
* You're thinking of a different author. Do you have any more information about the author, like their genre, any specific books they might have written, or even their approximate year of publication?
Could you please provide more information so I can help you find the author you're looking for?