Go back to directory. Add to Address Book. CASA of Southwestern Illinois CASA of Southwestern Illinois Contact: Mateja Sears 1801 North Belt West Belleville IL 62226 USAwork Work Phone: 618-234-4278work Work Fax: 618-234-4360workfax Work Email: casa.matejasears@gmail.comINTERNET Website: CASA of Southwestern IL Categories: Non Profit, Social Services Updated 4 years ago.