SOME CLUES FOR MYSTERY READERS.(BOOKS)

Byline: NANCY PATE

Steal time for these new paperback mysteries: ``A Certain Justice,'' by P.D. James (Ballantine, $7.99): With characteristic deliberation, James delivers an absorbing, intricate mystery in which the victim's life holds the clues to her death. Indeed, we get to know British barrister Venetia Aldridge well in the book's first 100 pages, which cover the last four weeks in her life. And so we also know there's no shortage of suspects when the contentious Aldridge is found stabbed to death at her desk, a bloodstained wig on her head. The enigmatic detective Adam Dalgliesh takes a back seat here to the fascinating cast, from an elderly barrister who's …