Greetings
Sources which contain information about African American in Essex County Virginia are as follows:

Certificates and physical descriptions of 339 Free Negroes, Essex County , Va 1810-1843, alphabetized by last and first names. Contact the Clerks Office for copies a small fee is charged if they find your ancesters.

Uprooted and Transplanted from Africa to America, Focus on African-Americans in Essex County, Virginia; Oppressions, Achievements, Contributions the 1600-1900s;1999; Lillian H. McGuire

Settlers, Southernes Americans, The History of Essex County Virginia,1984
Includes chapters pertaining to African Americans; free and in slavery: during colonial times, Antebellum Religion,politics
Chapter 5; Blacks in Antebellum in Essex County
Chapter 8; Liberation, reconstruction and reaction

Index to Marriages of Old Rappahannock and Essex Counties Virginia 1655-1900
Includes marriages between free people of color

Parish Record of the Christ Church, Middlesex County Virginia 1653-1812
Includes marriages, birth of free people of color and slaves affliated with the church
published by The National Soceity of the Coloniol Dames of America in the State of Virginia, 1897

Free Negro Heads of Families 1830; (Essex County Virginia p 181-182)Carter G Woodson