This is an older thread, but I've just got to add my "expertise" to the mix. Research is something I do and enjoy. I do it for treasure hunting and subsequently for writing about my "advertures." Some of the following has already been mentioned and explained by Jeffro and others, but here's my 2 cents 2 bucks worth of advice and experience.
There are basically three types of research materials. 1) Primary sources of information, 2) Secondary sources of information, and 3 tertiary sources of information.
1) I prefer the Primary Sources because they were written or created by people who were there. People who were CONTEMPORARIES of the times. They lived the life, they saw the events, they were the actual people at the time the things actually happened. Such resources would be personal journals (not rememberances or looking-back type stories), original maps, original photographs, deeds, wills, birth certificates. These are the most accurate things to use for research because they have not been corrupted or changed or misinterpreted through the years. They can have errors (misspelled names, wrong dates, etc.), but they will often be much more accurate than anything since then. These are the things that precipitate legends. They are the building blocks of legends (and hopefully of successful treasure hunting). These are the types of things that Mel Fisher investigated in Spain so that he had an accurate starting point in finding the Atocha. And that's all these primary sources are...they are starting points in your research. But without them, it is hard to get very far. It's like building a house...start with a good foundation. Without a good foundation, the whole house will be unstable. Same for doing research.
2) Secondary sources would be newspaper articles written by someone who wasn't there, but who gathered "facts" and then wrote them down for the newspaper on the same day the event happened. These are also known as second-person or third-person accounts. Other examples of secondary sources would be court documents, tax records, school yearbooks, wanted posters. These are things that may be contempories of the timeframe, but they were created by someone other than the person who was involved. They can be quite helpful in doing research, but they have now been "handed down" by someone else, so the possibility for error, exaggeration, or misunderstanding increases. Each time the information passes through someone's hands, the possibility for errors is increased.
3) Tertiary sources of information would be things like books and magazines that re-hash an old story. These may give a shred of useful information, or they may be quite accurate based on the information available to the writer at the time, but they are also the most likely to perpetuate or foment a legend or rumor. These types of resources would also include maps that have been made recently but that purport to show old buildings and locations. And of course the stories that start out, "my great granddad had a Wells-Fargo cash box buried on his land and he never dug it up." If the granddad himself had told you this, then that could be a primary source of information, but since his grandkid is telling the story years later, it's a tertiary source and would be interesting to hear but not something to hock the wife and kids over. The truly important portion of a tertiary source of information is the bits and pieces and hints that they may include or that you may gleen from them. The most notible of which would be the bibliography or footnotes listed in books. These notations and references could/should lead to more info and possibly some primary sources.
OK, so now you've done your research in the libraries and historical societies, the courthouses and archives. It's time to hit the spot yourself. Once you go to an area that may contain a buried treasure, you need to look at it from a very practical standpoint. And you need to put yourself in the other person's shoes. WHAT WOULD THEY HAVE DONE? Would they have traveled to town and gone to the bank to deposit their money, or would they have buried it in the gopher hole next to the old oak tree? Has the stream bed changed through the years (quite common event)? Has the soil been removed or brought in? What would you have done if the posse was on your trail? These types of questions are often the most interesting portion of the research because now you must "live" the other person's life for a little while.
You have reached the point in the process where you want to start the physical search. You've done your homework and you're ready to take the exam, so to speak. LUCK will now be your biggest asset. The treasure may have been claimed years earlier and never been reported, or the terrain may be so different that it's impossible to go any further (a reservoir may cover the area now, or a highway). But at least you gave it a good shot. And who knows, maybe you will have GOOD LUCK.
I've found three small caches in my lifetime. One was through diligent research, one was just by taking an educated guess when I got to a place, and one was just through pure dumb luck. None of them would ever make the record books, but they would probably make anybody here feel the time and trouble was worthwhile. I felt great satisfaction when my efforts panned out. I also learned some valuable lessons: gold and silver aren't the only rewards of a treasure hunter, being in somebody else's shoes--even for a short time--is enlightening, and the historical information learned from doing the research was much more interesting and extensive than anything I ever learned in college.
I hope you, too, find your own Atocha someday, whatever that may be for you. GOOD LUCK!
