Big Story, Peter Braestrup's account of how the American press and television reported and interpreted the 1968 Tet crisis in Vietnam, is now available as an Anchor Reprint [$8.95]. John McPhee's The Pine Barrens has been republished in paperback by Farrar, Straus & Giroux [$2.95]. Beacon has a paperback edition of Howard N. Meyer's XIV, The Amendment That Refused to Die [$5.95]. Massachusetts is offering a new hardback edition of Ronald M. Peters, Jr.'s The Massachusetts Constitution of 1780, A Social Compact [$15.00], Dee Brown's saga of the westward movement of American railroads, Hear That Lonesome Whistle Blow, is a recent Bantam Book [$2.50], and Roger Kahn's A Season in the Sun has been reprinted as a Berkley Book [$1.95],