Another great online guide to Genealogical Records.

Some gems under the "Slavery, Free People of Color & Freedmen" topic:
1) "List of Slaves Imported for Sale in the City of New Orleans, 1831"
[Indexed in a LA Genealogical Publication]

2) "Declarations of Individuals Importing Slaves into New Orleans, 1831-1833"
[These 'declarations' were required by law in many Southern parishes/counties across the US.]

3) "Passports, 1818-1831"
[Not your average 'passports'. These were given to free people of color wanting to leave / re-enter the local community, or those wanting to bring their enslaved out of (and back into) the city. Other areas instituted a similar policy.]

4) "Emancipation petitions, 1813-1843"

5) "Petitions for the Emancipation of Slaves, 1827-1846"

.... and more