Don't feel obliged to pay ""suggested"" contributions, do take the Culture Bus, and yes, the World Trade Center elevators shake near the top. A lot. Helene Hanff's dry Manhattan is another irreverent tour de force, as idiosyncratic and cordial as 84, Charing Cross Road, with a similar cumulative lilt. Her New York comes complete with rush hour crush, evidence of vandalism, bureaucratic runarounds, and incomparable felicities. Friend Patsy Gibbs serves as perfect foil, a West Sider to her East Side moorings, Harvard to her high school education, unofficial organizer and inveterate newspaper clipper to Hanff's cheerful-scatterbrain facade. Both dislike heights, overlook street signs, relish the unexpected, and slyly kick in a little history at each site. And they skip some of the usual must-sees in favor of more clarified choices: the Morgan Library and the Frick instead of MOMA and the Metropolitan. Hanff agrees to visit Zabar's, Gibbs to walk through Bloomingdale's; they try the tram to Roosevelt Island, a Harlem tour bus, a stroll through Riverside Park. The banter is casual and unforced, without the affectations of the Hayes-Loos Twice Over Lightly; and their approach has none of the exclusive airs of New York on $500 a Day or the recent collaborative New York, N.Y. A genteel, happily disorganized ruckus: it won't be everyone's ideal--most tourists will find it too gadabout--but it certainly appreciates local conventions.