There are 10 US Post Offices in Pulaski County serving a total of 6,779 residents equating to 678 residents per post office. It's estimated that approximately 10,820 packages are handled across the 10 county post offices annually. Pulaski County is a county located in the U.S. state of Illinois. According to the 2010 census, it had a population of 6,161. Its county seat is Mound City. It is located along the Ohio River in the portion of the state known locally as \"Little Egypt\"."