Bureau County, IL Genweb Project a collection of online resources for genealogy researchers
Bureau County Surnames
Census-Online.com - census transcriptions for  Bureau Co.
Illinois Public Domain Land Tract Sales Database - for Bureau County select this county and then enter the surname (at least first 2 letters) of the person whom you wish to search on  (a government database of over 550,000 19thC land sales in Illinois - info on obtaining original copies is here )
Civil War Rosters
The Tombstone Transcription Project - cemeteries for Bureau Co. IL
US GenWeb Archives for Bureau County cemeteries, newspapers, wills, military rosters etc recorded online

Additional Resources

Ilinois Newspaper Search enter your ancestor's name to instantly search the world's largest newspaper archive; over 12 million newspaper pages
Illinois Birth Records
Illinois Marriage Records
Illinois Divorce Records
Illinois Death Records