Clara Laughlin's So You're Seeing New England (Little Brown, May 9th), parallels this book fairly closely, and is, I suppose inevitable. Too bad -- for both are good and only one is really needed. This is a better book for those to whom New England is wholly new territory, so bookshops west of the Mississippi should sell this to their eastbound customers. It actually covers such things as climate and clothes! There is an additional feature in the survey at the end of each state, giving salient facts -- boundaries, population, principal cities, etc. And there is an appendix of planned tours, again keyed to the traveler from a distance, along with lists of towns, hotels, prices -- and for winter visitors, lists of places with ski jumps and tows.