Of 102 counties in the Inland Empire, Warren County ranks 49th by size (543 square miles). Warren County is in Western Illinois. The total value of nearly 1,000 acres of lakefront homes and property recently listed for sale in Illinois's Warren County was almost $400,000. Browse all waterfront property for sale in Warren County on the Land Network to find the marina, lakefront and other recreational property that meets your needs, from waterside land perfect as a retirement investment to existing residential waterfront land and property for hunting, fishing and other outdoor-recreation pursuits! The most common type of land for sale by combined acreage in Warren County is residential property.