The Metropolitan Museum of Art, as I've stated before, has a very good archive of past exhibitions. This particular exhibit, which appeared in 2006, has a very modest home page which includes some quite nice links. For instance, the audio file has an informative interview with Kara Walker (this Wikipedia entry has some very good links). The images are rather limited, but a search on the site will turn up a few more. The "Learn More" link has a bit more detail, but doesn't include links to the two works by other artists that are mentioned.
One is The Gulf Stream by Winslow Homer and the other is The Deluge towards Its Close by Joshua Shaw. Both can be zoomed in on and the detail is still really good at close magnifications. Walker talks about "The Gulf Stream" in her interview, so it's a good idea to listen to that while viewing the painting. She also discusses Dressing for the Carnival, by Homer, which is well worth zooming in really closely on, to see the faces of the people, especially the children, standing around the central figure.
