GREENWOOD, Mississippi (AP) -- In the Mississippi Delta, life is never far from the blues -- a challenge and an opportunity for those promoting tourism here. Already, millions of people visit, drawn by nine casino resorts in Tunica County that pump more than $2 billion a year into the region's economy. But a short drive and a world away lies the real Delta -- stretching from just beyond the glitzy gambling halls all the way to the magnolia-shaded lanes of Natchez. Here, amid some of the nation's richest soil and poorest people, are the sharecroppers' shacks, cotton fields, small towns...