With decades of research in all paranormal subjects, I built up books and equipment that helped immensely. I want to share these with you and explain why these are important.
Ancient Giants -
Books are your best resource here. The #1 source I found was books by early explorers. The first European arrivals at remote locations encountered locals and their legend, if not giant people still remaining.
Here's some of my favorite book references -
The Smoky God by Willis George Emerson
This book deals with the Hollow Earth and a long-ago encounter two fisherman from Norway experienced when their ship went off course.
The Natural and Aboriginal History of Tennessee by John Harwood.
This was my very favorite reference book as it documented finds from the 1700s, a time before the government institutions were put in place to shut up talk of giants. It documents large finds of little people graves and giants too. I bookmarked and highlighted the book like crazy.
Relation of the Discovery and Conquest of the Kingdoms of Peru by Francisco Pizarro
This is a compilation of notes and information put together to demonstrate Pizarro's discovery of Peru.
Famous Voyage of Sir Francis Drake by Francis Drake.
This English explorer and privateer was the second person to circumnavigate the globe. Along the way, he had first contact with may people.
Start looking into explorers who first landed in places like Andaman Islands (Marco Polo), Patagonia (Fernando de Magallanes), and the South Pacific Islands.
Anything by Jim Vieira is a fantastic find, as this stone mason turned forensic archaeologist is hot on the dead tracks of the Ancient Giants. Try his book with Hugh Newman, Giants on Record: America's Hidden History, Secrets in the Mounds, and Smithsonian Files.
A must-have book that has an enomrous catalog of actual clippings and documented info is The Ancient Giants Who Ruled America by Richard Dewhurst.
Study what Thor Heyerdahl found out on Easter Island about the "long-earreds."
The explorers who found Patagonia ran into some very odd fellows there.
The Caribeean has stories of giants on islands.
The Solomon Islands still speak of giants in their mountains.
Learn about Wisconsin's ancient mining that the local indigenous people claim, they did not mine, but people from the North did. The tools found there were unusually large, as well as the tribe mentioning that they had a strange way of making rocks break to mine.
The tools found in Great Orme Mines in Wales were tremendous. Check out that path.
Of course, Lovelock Cave, is probably one of the most infamous locations of giants. The Humboldt Museum is apparently forbidden to speak of giants, but they have in the past housed giants skulls and a giant skeleton.
Aboriginal people have a legend of two women who trap a giant in a cave and burn the entrance to asphixiate it.
Paxson Hayes in the 1930s in the Sonoran Desert of Mexico comes across a lost city of giants.
The Grand Canyon is said to house a cave an explorer came upon that had dead soldiers and lots of treasure.
It is said that there were giants in underground tunnels in Death Valley's Panamint Mountains, hiding treasure within. This can be found in the book Death Valley Men by Bourke Lee.
The Bible has a source people often refer to, claiming Nephilim and other giants existed in the past.
Anyone who decides to head out and try to find evidence of giants should know there is a law in America that anything ancient is handed over to the local tribes.
Mining sites, caves, and underground caverns are most likely locations, as well as suspicious mounds, but some advice - If you go forth, document live video on social media if you can. Show the discovery without touching it. Don't move anything. Just document, photograph, and if you want, use taper measures, but leave it pristine. Then, call on authorities to claim it. If you can, get a card or number from whoever is managing the recovery. Months later, check in with that person. Document that. Keep doing it. See what happens (or doesn't) to the find. This is a good example of how it goes "missing."
Happy researching!