By CLARE McHUGH January 16, 2008 A cursory description of Geraldine Brooks's "People of the Book" (Viking, 384 pages, $25.95) might make the novel sound like a distaff, Jewish version of "The Da Vinci Code." That's because Ms. Brooks, who won the Pulitzer Prize for her last novel, "March" (2005), has now produced a historical mystery starring a strong-willed heroine determined to ferret out the truth about a valuable medieval Hebrew manuscript nearly lost and then found again in war-torn Bosnia. In reality, "People of the Book" is of much more substance than Dan Brown's overwrought, silly, and ultimately distasteful thriller could ever hope to be — yet Ms. Brooks's work is just as entertaining. She has accomplished something remarkable, fashioning a story that is compelling and eminently readable, even as she maintains high intentions and an earnest purpose. As it follows the imagined journey of the Sarajevo Haggadah, an illuminat