Links

Major Collections & Societies

Ancestry.com $
FamilySearch
MyHeritage $
Geni $ - owned by MyHeritage
Fold3 $ - Owned by Ancestry.com, focuses on military records, digitized pension files, etc.
FindMyPast $ - especially strong in UK records, includes the PERSI database
Cyndi's List - A comprehensive, categorized & cross-referenced list of genealogy-related links

AmericanAncestors $ - New England Historic Genealogical Society (NEHGS) digital collections, including many journals (NEHGR)
New York Genealogical & Biographical Society $ - (NYG&B), with archives of the Record - (NYGBR)
National Genealogical Society. $ - (NGS), including archives of the Quarterly (NGSQ)
The National Archives UK
The Statue of Liberty - Ellis Island Foundation - Ellis Island passenger lists
Association of Professional Genealogists
Board for Certification of Genealogists

GenGophers - extensive, searchable collection of digitized family history books
HathiTrust - a collection of millions of titles digitized from libraries around the world.
Google Books - the world's most comprehensive index of full-text books.
Archive.org - non-profit library of millions of free books

ItalianGen - free databases especially for New York City
NYC Marriage Index - searchable database of the 3,124,595 marriage licenses filed in New York City between 1950-1995
Missouri Digital Heritage - 9 million records, including scanned Missouri Death Certificates from 1910 - 1961
Early Bergen County Families / Pat Wardell (Offline! )

JewishGen - thousands of databases, research tools and other resources to help those with Jewish ancestry research
Jewish Records Indexing - Poland - millions of records from more than 550 Polish towns indexed and searchable online
Yad Vashem Digital Collections - World Holocaust Remembrance Center