We need to be consistent with research. Don't leave out any steps in the research process and when records are found or not found, document the information. Keep a log of where you have researched and be sure to note that you did not find anything in a specific record. Time is wasted when you have to repeat research. Genealogists are usually not very patient and we have to learn how to be persistent. Our research needs to be continuous and without falter. Never give up. Eventually you will find the record needed or enough information to make inferences.
Looking at genealogical forms, the basics are name (given and surname), date and place of birth, date and place of marriage (if married), date and place of death, date and place of burial. Those basics mean setting a goal to retrieve vital records. This can be done by checking the typical birth, marriage and death records kept within county or state jurisdictions. Simple, until you hit the brickwall.
The answer is in the previous paragraph, "county or state jurisdictions." Do you know where your ancestor lived? Are you assuming that he or she lived there? Genealogists have to assume in order to project research ideas and goals, but when that assumption fails, do not give up.
Recently a genealogist contacted me with information stating that his ancestor was married in 1832 in Watauga County, North Carolina. Not so! The 1832 may be correct, but Watauga County was not a county in 1832. It was formed in 1849 from the counties of Ashe, Caldwell, Wilkes and Yancey. Since Yancey was created in 1833, we can eliminate that as a possibility for finding the marriage record in that county, assuming 1832 is the correct year. Caldwell County was formed in 1841, thus we can eliminate that county. Ashe County was formed in 1799 from Wilkes County which was formed in 1777. Those are two counties that we need to research for the marriage record.
How did I know all these dates and counties? I didn't pull them out of my head and while I could probably find that information with a little digging and searching on Internet, I used a book. They are still necessities of genealogical research. Some that I like and have are:
Redbook, American State, County, and Town Sources, 3rd ed., edited by Alice Eichholz, Ph.D., C.G., published by Ancestry, 2004 (earlier editions are acceptable and may be found in genealogical libraries)
The Family Tree Resource Book for Genealogists, edited by Sharon DeBartolo Carmack and Erin Nevius, published by Family Tree Books, 2004.
The Handybook for Genealogists, 11th edition, published by Everton Publishers, 2006 (earlier editions are acceptable and may be found in genealogical libraries)
The same books also explain when the states and counties began the recording process of vital records, along with addresses of state and county institutions where the records are kept. Notations are usually made concerning the loss of records. Information on state kept vital records can also be found online at Vital Records Information for United States.
Knowing where to look is important, but perhaps your elusive ancestor did something totally different, such as not going to the courthouse to record the death of his wife. In that case a search of other documents will be necessary. Consider obituaries or newspaper articles, church records, cemetery and burial records, family Bibles, old letters, diaries and journals. The brickwall will not be quite as high if you dig into these resources.
In an attempt to establish where an ancestor was actually living, you need to use land records. The above three books, plus the various resources available on Internet assist in this process. Checking the web page of the Bureau of Land Management General Land Office Records at Bureau of Land Management, will provide information if your ancestor obtained land from the federal government. Be sure to read the instructions and information about federal land patents on this site. If he or she did not obtain land from the federal government, start checking land records in the states and counties where you believe they lived.
As you have surmised by now, not everything is available on Internet. You will have to write letters or obtain records on microfilm through Family History Centers (LDS). For more information on this process, check out the FamilySearch web page at FamilySearch International.
The entire world is at your fingertips, but you must be persistent and consistent. Time is on your side as more and more records are being digitized and made available on Internet. However, in the meantime do your homework and start tracking those elusive ancestors by using the tried and true methods we learned years ago.