Starting in 2002, Spokane, Wash., journalist Sherry Jones toiled weekends on a racy historical novel about Aisha, the young wife of the prophet Muhammad. Ms. Jones learned Arabic, studied scholarly works about Aisha's life, and came to admire her protagonist as a woman of courage. When Random House bought her novel last year in a $100,000, two-book deal, she was ecstatic. This past spring, she began plans for an eight-city book tour after the Aug. 12 publication date of "The Jewel of Medina" -- a tale of lust, love and intrigue in the prophet's harem.

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