Start with what you know
Write down every name, place, and date you've heard from family. Aim back to the 1940s before you touch a database. Interview the oldest living relatives — they have details no record will give you.
Find the 1870 wall
1870 is the first census after emancipation in which Black Americans appear by name. Locate your ancestor there using the National Archives or Ancestry. Note neighbors with the same surname; many were related.
Cross over to slaveholder records
The 1860 and 1850 Slave Schedules list enslaved people by age and sex, not name, but the owner is listed. Match the owner's surname to your ancestor's, then dig into that white family's records — wills, deeds, plantation ledgers, the Freedmen's Bureau marriage and labor contracts.
Use the new tools
The International African American Museum's Center for Family History (Charleston) does free research consultations. AncestryDNA + 23andMe match against millions of African-American profiles. The Beyond Kin Project teaches how to add enslaved ancestors to family trees.