MEDICINE LODGE, Kan. (AP) — Prospectors are punching holes across south-central Kansas in the hunt for oil and gas that players say could yield big returns not just for drillers but also for the state's economy. In county courthouses across much of Kansas, scores of researchers comb through dusty land records as producers and speculators alike scramble to snap up millions of acres of mineral rights. Leases which just three years ago went for $30 an acre are now fetching $3,000 an acre in drilling hotspots. Awe-struck real estate agents watch incredulously as mineral rights fetch higher prices than the land itself. Drilling has only just begun. Barber and Harper counties are "ground zero" of an oil boom anticipated to spread north across a wide swath of the central Kansas prairie.