Orange County, CA Genweb Project a collection of online resources for genealogy researchers
Orange County California Genealogical Society, OCCGS
Orange County, CA Genealogy Forum read and post messages about your ancestors for this county
Orange County Message Board read and post messages with other genealogy researchers of this county
South Orange County Calif. Genealogical Soc
The Tombstone Transcription Project - cemeteries for Orange Co. CA
US GenWeb Archives for Orange County cemeteries, newspapers, wills, military rosters etc recorded online

Additional Resources

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