Pro-Tip: Many of the paid resources below can be accessed from some local libraries for free.
Run by the LDS church, many, but not all, of the records available on Ancestry can be accessed for free here. Visiting their Family History Centers in person can also unlock many more records. Unfortunately, the user friendliness of the site and search engine power don't match Ancestry.
If your goal for DNA testing is to find relationships and confirm your family tree, Ancestry DNA has the largest database in the world. Once tested at Ancestry, you can download your raw DNA file and update it to sites like MyHeritage, FamilyTreeDNA and Gedmatch for free. Raw files cannot be uploaded to Ancestry.
If you're looking to DNA test to get information on your health, 23andMe far outpaces Ancestry in this department. You can download your raw DNA file and upload it to sites like MyHeritage, FamilyTreeDNA and Gedmatch for free. Raw files cannot be uploaded to 23andMe.
While the vast majority of the records on MyHeritage can be found elsewhere for free, the site does have one of the best photo correctors around, as well an automatic colorizer for black and white photos that works surprisingly well.
This free site isn't always 100% reliable as it's user generated data, but you can often little treasures here beyond the burial location of your ancestors. You can even put in requests for volunteers to photograph headstones.
Fold3 is the major repository of military records for the USA. It is subscription based, but since military records normally only needed on occasion, check with your local library first to see if you can access it for free.
If you're looking for personal details about your ancestors, local newspaper articles are a nearly unbeatable source. Newspapers.com has the advantage of being able to connect and directly save clippings to your Ancestry tree.
There's another player in the digitized newspaper game, which is newspaperarchive.com. There is some overlap between the two main newspaper sites, but there is enough difference that you should consider searching both.
Run by the Italian national archives system, this site contains many microfilmed records organized by region and town for free. Most records are not searchable, so it is necessary to review them page by page. Some records do have a hand-written index at the end, however.
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