I don't think you'll get too far. There aren't any "clear channel" frequencies (not the company, the 500,000 watt AM stations like WCCO and WBAP) left. Just googling 1380 AM, there are at least three stations already asigned 1380 you'd have to buy out. Normal starting price for a radio station was 5x the yearly earning, at least that was the formula 20 years ago.