One way to find scholarly monographs on your subject is to browse the shelves in an area where related works are located. The "Class" (classification) links below provide greater description of some relevant classes. Monographs on these topics are on the 3rd and 4th floors of Cabell Library, but you can also browse for reference titles on the 1st floor.
Class E - History of the Americas
E184.5-185.98 Afro-Americans
E185.2-185.89 Status and development since emancipation
E185.96-185.98 Biography. Genealogy
E441-453 Slavery in the United States. Antislavery movements
Class H - Social Sciences
HT1501-1595 Races
Including race as a social group and race relations in general
Class P - Language and Literature
PN841 Black literature (General)
--BUT works about individual authors are located in the Library of Congress Class for their region and period
Dissertations may be useful for finding criticism on newer authors or specialized topics, and the bibliographies of recent dissertations can often provide a wealth of new sources.
If you can't find the book that you want at VCU, try these resources to find what you need.
E-books can be found via the VCU Libraries Search. Here are a couple resources that may be of particular use.
Reference books provide brief descriptions of people, places, events, and so on, often along with suggestions for related secondary or primary sources. To browse for reference books, use the outline above and go to the stacks on the 1st floor of Cabell Library.
The African American National Biography by 
Encyclopedia of African American history, 1896 to the present : from the age of segregation to the twenty-first century by 
Encyclopedia of African American Artists by 
Encyclopedia of the Harlem Renaissance by 
Black Literature Criticism : Classic and Emerging Authors Since 1950 by 
The African American Almanac by 
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