Clark County Extension Office - Branch office of Ohio State University, it combines the needs of local citizens and communities, with new research and technical information. Clark County - Government directory, court and zoning information. Springfield - Clark County Chamber of Commerce. - Complete listing of area events, business, lodging, history and activities. County Map - Ohio Department of Transportation map of Clark County. Profile for Clark County - Information on the political infrastructure of the county. Clark County Sheriff's Office - Provides profile of department, law enforcement programs, crime statistics and history.