An extended valentine to an actress we've all fallen in love with at least once. While many actors fail to live up to their publicity, Audrey Hepburn seems, by all accounts, to have been as genuinely charming, and stylish, and wistful, and kindhearted as she appears on-screen. Of course, life wasn't always kind. There were two divorces, miscarriages, professional disappointments, and unsettled memories from her childhood in wartime Holland. But mostly, she enjoyed herself well enough, playing mother to her children and a succession of adored dogs, tending her own garden in her Swiss retreat, and doing good-will work for UNICEF. Movies were all right as far as they went, and though she made a few classics such as Funny Face and Breakfast at Tiffany's, she had no overwhelming passion for them (like Garbo, she made only 26 films). Despite winning an Oscar for Roman Holiday, she was not a particularly gifted actress, best suited, like John Wayne, to playing versions of herself. But she had presence and style, and with the able assistance of the designer Givenchy, defined fashion for almost a generation. Whether this all adds up to an interesting biography is another question. Hepburn herself once declared, ""There's never been a helluva lot to say about me."" Veteran Hollywood biographer Paris (Garbo, 1995, etc.) does his unlevel best to prove her wrong, but he is only partly successful. He is too much the fan, too much in awe of ""Audrey."" Paris rarely goes even as deep as an attempt to capture the evanescence of a screen persona, preferring instead the appointment-book surety of times and places and people. Still, all the facts are in the proper places, pleasantly displayed, and easily accessible, and that's more than can be said for most show-biz bios.