Clarke County Assessor 100 S Main St Osceola, IA 50213 Phone : (641) 342-3817 Business Category Public Finance Taxation & Monetary Policy Counties Of-iowa--clarke County Of, Assessor Courthouse Osceola, IA 50213 Phone : (641) 342-3817 Business Category Government Offices-County Government Offices & Public Schools Clarke County Offices Courthouse Osceola, IA 50213 Phone : (641) 342-3817 Business Category Government Offices-County Government Offices & Public Schools