$ Weeks This On Week List Fiction 1 6 THE ICARUS AGENDA, by Robert Ludlum. (Bantam, $5.95.) A Congressman's secret dealings with terrorists may bring him the Presidency - or death. 2 11 THE SHELL SEEKERS, by Rosamunde Pilcher. (Dell, $4.95.) A woman and a painting tie together three generations of an English family. 3 2 TAPESTRY, by Belva Plain. (Dell, $4.95.) The changing fortunes of a New York banking family between the two world wars. 4 1 THE DRAWING OF THE THREE, by Stephen King. (Plume/NAL, $12.95.) Continuing the horror story begun in ''The Gunslinger.'' 5 * 1 PEOPLE LIKE US, by Dominick Dunne. (Bantam, $4.95.) The rivalry of two clans in New York society and one man's role in it. 6 2 PRELUDE TO FOUNDATION, by Isaac Asimov. (Bantam, $4.95.) An overture to the science fiction saga about the Foundation empire. 7 1 LOVE IN THE TIME OF CHOLERA, by Gabriel Garcia Marquez. (Penguin, $8.95.) A Colombian poet's perdurable love for a woman is tested by life's changing conditions. 8 * 2 TEXAS FURY, by Fern Michaels. (Ballantine, $4.95.) From the oil fields of the Lone Star State to Tokyo and Switzerland; a family saga. 9 3 SILVER TOWER, by Dale Brown. (Berkley, $4.95.) The superpowers edge toward high-tech war in the Middle East in 1992. 10 1 DOUBLE, DOUBLE, by Michael Jan Friedman. (Pocket, $3.95.) A new ''Star Trek'' novel. 11 25 LONESOME DOVE, by Larry McMurtry. (Pocket, $4.95.) The Old West seen larger than life. 12 11 INHERITANCE, by Judith Michael. (Pocket, $5.50.) The jealousies and rivalries of a wealthy family on Boston's Beacon Hill. 13 1 FREAKY DEAKY, by Elmore Leonard. (Warner, $5.95.) Survivors of the tumultuous 1960's, determined to keep the revolution alive, embark on a crime spree. 14 * 20 THE BONFIRE OF THE VANITIES, by Tom Wolfe. (Bantam, $5.95.) A bond trader caught in the jungles of New York. 15 7 THE LAST PRINCESS, by Cynthia Freeman. (Berkley, $4.95.) A socialite sacrifices a family fortune and a wealthy fiance to marry for love. Weeks This On Week List Nonfiction 1 2 BITTER BLOOD, by Jerry Bledsoe. (Onyx, $4.95.) Nine murders in three wealthy families connected by obsessive love and custodial conflicts. 2 6 THE PRIZE PULITZER, by Roxanne Pulitzer with Kathleen Maxa. (Ballantine, $4.95.) Life in Palm Beach's steamy rich society. 3 * 47 LOVE, MEDICINE & MIRACLES, by Bernie S. Siegel. (Perennial/Harper & Row, $8.95.) The importance of a patient's mind and emotions. 4 17 CHAOS, by James Gleick. (Penguin, $8.95.) A ''new science'' that makes it possible to see order and patterns in what appears to be erratic. 5 * 286 THE ROAD LESS TRAVELED, by M. Scott Peck. (Touchstone/S&S, $9.95.) Psychological and spiritual inspiration by a psychiatrist. 6 17 TRUMP: The Art of the Deal, by Donald J. Trump with Tony Schwartz. (Warner, $5.95.) The career and business style of the New York entrepreneur. 7 44 THE POWER OF MYTH, by Joseph Campbell with Bill Moyers. (Doubleday, $19.95.) The ways in which mythology illuminates the stages of life. 8 1 CONTRACT ON AMERICA, by David E. Scheim. (Zebra, $4.95.) Evidence suggesting that the Mafia was responsible for President John F. Kennedy's assassination. 9 11 ALMOST GOLDEN, by Gwenda Blair. (Avon, $4.50.) The rise and fall of the television anchorwoman Jessica Savitch. 10 7 BATTLE CRY OF FREEDOM, by James M. McPherson. (Ballantine, $14.95.) A history of the American Civil War era. Weeks This On Week List Advice, How-to and Miscellaneous 1 4 YUKON HO! by Bill Watterson. (Andrews & McMeel, $6.95.) More ''Calvin and Hobbes'' cartoons. 2 38 CODEPENDENT NO MORE, by Melody Beattie. (Hazelden/Harper & Row, $8.95.) How to solve your own problems while caring for other people's afflictions. 3 8 SWIM WITH THE SHARKS WITHOUT BEING EATEN ALIVE, by Harvey Mackay. (Ivy, $4.95.) Strategies for succeeding in business. 4 14 RAND McNALLY ROAD ATLAS. (Rand McNally, $6.95.) The 1989 edition of a guide to the United States, Canada and Mexico. 5 * 4 GARFIELD CHEWS THE FAT, by Jim Davis. (Ballantine, $6.95.) Cartoons about a fat cat. These listings are based on computer-processed sales figures from 3,000 bookstores and from representative wholesalers with more than 38,000 other retail outlets, including variety stores and supermarkets. The figures are statistically adjusted to represent sales in all such outlets across the United States. *An asterisk before a book's title indicates that its sales, weighted to reflect the book-selling industry nationally, are barely distinguishable from those of the book above.