For more information about the African power figure and its context, see the link below from the Brooklyn Museum:
http://www.brooklynmuseum.org/collections/african_art/22.1421.php
This link takes you to information about that museum's entire collection:
http://www.brooklynmuseum.org/collections/african_art/
Just twenty five years after Heart of Darkness' serialization, the Brooklyn Museum presented an exhibit of African art. At this time, this art was influencing European artists such as Picasso.
http://www.brooklynmuseum.org/research/digital-collections/pna1923/
Closer to home, here are some links to the Smithsonian's Museum of African Art:
http://africa.si.edu/exhibits/africanvision/index2.html
http://africa.si.edu/collections/index.htm
In 1993, the Bayly Museum of Art at the University of Virginia set up an electronic exhibit on African art:
http://www.lib.virginia.edu/clemons/RMC/exhib/93.ray.aa/African.html
NYC has a Museum for African Art. Currently, it is based in Long Island City, but it will soon be moving to a new home in Manhattan.
http://www.africanart.org/index.php
The Guggenheim Museum includes a searchable map of Africa on its web site. Here are links to its pages on Central Africa (the region where the Congo is) and Western Africa (the region where Senegal and Nigeria are).
http://artnetweb.com/guggenheim/africa/central.html
http://artnetweb.com/guggenheim/africa/west.html
The Guggenheim also has a page on African film. Unfortunately, it seems to have been written in the 1990s:
http://www.artnetweb.com/guggenheim/film/
Here is some background information on African art from a web site at Sweet Briar College in Virginia:
http://www.uiowa.edu/~africart/teachers/Chronology.html
http://hum.lss.wisc.edu/hjdrewal/Looking.html
http://hum.lss.wisc.edu/hjdrewal/aesthetics.html
Anne-Marie O'Connor from the LA Times writes here about the ongoing reassessment of African art:
http://www.calendarlive.com/galleriesandmuseums/cl-et-africanart29jan29,0,5808956.story
This is a little off topic, but I thought that you might be interested in this essay on African history from NYC's Metropolitan Museum of Art:
http://www.metmuseum.org/toah/hd/ahis/hd_ahis.htm
I'd like to close with a site from Senegal's DAK'ART Biennale. It is in French. The next exhibition will be this summer, so if you plan to go to Dakar....
http://www.biennaledakar.org/