The Post reports this morning on impressive growth throughout the region in the number of black-owned businesses. Census Data released yesterday detailed the strides black businesses made between 1997 and 2002; nationally black-owned firms grew 45 percent (compared to about 10 percent for all firms), but they still only account for 5 percent of all businesses. While growth took pace across the region, media focus has been on Prince George’s County, which now has…