National Trails System Willing Seller Act

National Trails System Willing Seller Act - Expresses the sense of Congress that in order to address problems involving multijurisdictional authority over the National Trails System, the Secretary of the Federal department with jurisdiction over a national scenic or historic trail should: (1) cooperate with appropriate State and local officials and private persons to pursue the trail's development; and (2) be granted sufficient authority to purchase lands critical to the completion of such trail from willing sellers.Amends the National Trails System Act to provide that, with respect to the North Country, Ice Age, and Potomac Heritage National Scenic Trails, no lands or interests therein outside the exterior boundaries of any federally administered area may be acquired by the Federal Government for such a Trail except with the owner's consent.