The county seat of Will County, IL is Joliet.
According to the NACo, the county seat of Bureau County, Illinois, is Princeton.
Orland Park, IL is located in Cook county.
Actually, Wheeling, IL sits on the border of Cook County and Lake County. Most of Wheeling is in Cook County, but some of Wheeling does lie in Lake County.
Fairfield, IL is located in Wayne county. It is the county seat.
Half is in Du Page County half is in Cook County.
Schaumburg IL, is located in Cook county.
Cook County
Oak Park is in Cook County. It is where Frank Lloyd Wright lived for a time. Edgar Rice Burroughs (author of Tarzan) was born here.
Carmi is located in White County, Illinois. It is also the county seat of White County.
Cook County is where Chicago, IL is located.
Tinley Park, Illinois is in Cook County.