'Oak Brook, IL' definitions:

Oak Brook, IL -- U.S. village in Illinois

From: Gazetteer 2000
Name :
Oak Brook, IL -- U.S. village in Illinois
Population (2000) :
8702
Housing Units (2000) :
3258
Land area (2000) :
8.160527 sq. miles (21.135666 sq. km)
Water area (2000) :
0.096787 sq. miles (0.250678 sq. km)
Total area (2000) :
8.257314 sq. miles (21.386344 sq. km)
FIPS code :
54534
Located within :
Illinois (IL), FIPS 17
Location :
41.840180 N, 87.953079 W
ZIP Codes (1990) :
60521
Note :
some ZIP codes may be omitted esp. for suburbs.