The 1900 and 1910 censuses lists the number of years of marriage for each married household member.
Be aware that many documents are only available through a courthouse. Not everything is available online. If you can’t go personally, write a letter, or check with a nearby genealogical society which may provide a lookup service for a small fee.
Start with yourself. Document everything you know about yourself. Include your spouse, children, grandchildren, etc. Include occupations, where you have lived and all important events in your life. Then, and only then, start working backwards and with your living relatives.
Correspondence Record: is important to keep track of those with whom you have corresponded, the reasons for writing, and whether or not you have already received an answer.
[Charts & Forms]
Make a list of all living relatives before you start your genealogy research. Interview as many of them as possible. Be prepared with a list of questions. Use a tape recorder for the answers or take very good notes. Respect the person's privacy.