Both published and unpublished family history research can be found at public libraries and elsewhere. Also, visit or write to the public libraries where your relatives once lived. When writing, always enclose a stamped, self-addressed envelope, and make no more than three specific requests. Other sources of family books or genealogical research include historical societies, genealogical libraries, family organizations, etc. Review all published genealogies with a watchful eye as most contain some inaccuracies.
Many libraries have extensive collections.
Be sure to check thoroughly for sources such as city directories, local history books, newspapers, school yearbooks, plat maps, church histories, gazetteers, military records and cemetery records. Vital records are those birth, marriage, divorce and death records which all states have required to maintain since 1900. You can find them at state record offices, in some town archives and most county courthouses. You will find most church records filed in their church offices. If a church no longer exists, write the denominational headquarters.