There are a wide variety of local history and genealogy resources available online for free.
Vigo County Online Indexes: Online index of Vigo County obituaries; images of marriage records
Illinois State Archives: Many online databases to search.
Ancestry.com Library Edition : Available inside the library.
Cyndi's List : A comprehensive list of genealogy related websites.
Roots Web : Many resources available here - state sites, message boards, and more.
Family Search : Many records available.
MyHeritage.com : Free family tree building website.
Find A Grave: Virtual cemetery.
Bureau of Land Management Land Records : Offers images of original land patents.
Clark County Rootsweb and Genealogy Trails
1883 History of Clark County
Clark County Military Database: Compiled by Jeff Veach, local author of Rally Cry!: The Hometown Boys
in the Civil War