USA.GOV: State and Local Government
http://www.usa.gov/Government/State_Local.shtml
Government resources for state and local government employees, formerly known as "U.S. State & Local Gateway".
USA.GOV: Statistics at the State and Local Levels
http://www.usa.gov/Government/State_Local/
Statistics.shtml
Links to various online statistical resourses for all the states - including Illinois.
USA Counties
http://censtats.census.gov/usa/usa.shtml
USA Counties is the most comprehensive source for data on counties in the United States, featuring over 5,900 data items for the United States, States and counties from a variety of sources.
Census of Governments: Federal, State and Local Governments
http://www.census.gov/govs/www/
Access to mostly statistical information on various levels of governments, including employment, finance/tax data and Census of Governments (conducted every 5 years.)
State and Local Government on the Net
http://www.statelocalgov.net/index.cfm
The State and Local Government Internet directory.
Open Government Guide
http://www.rcfp.org/ogg/index.php
The Open Government Guide, formerly called "Tapping Officials' Secrets," is a complete compendium of information on every state's open records and open meetings laws. Published by The Reporters Committee for Freedom of the Press.