I'm reading Gerard Prunier's book Africa's World War right now. It begins with a discussion of the Rwandan genocide and draws on, but also amends in interesting ways, his earlier book, The Rwandan Crisis: History of a Genocide. Here's a review of that book.
Prunier is a highly readable academic, which means he doesn't use too much jargon and writes in an accessible and clear way -- this is actually quite unusual among the scholarly set. But if you venture into Africa's World War be forewarned: he does assume familiarity with this subject. And, as the 15th anniversary of the genocide approaches, it's well worth investing some time and effort to try to understand why what happened Rwanda in 1994 and why. It is a complex and deeply troubling piece of human history, but Prunier's work helps us understand the darker aspects and how the genocide affected later events.
Here is an interview with Prunier done by PBS. Based on the earlier book, I found it to be a good introductory discussion of the social dynamics in Rwanda. Recommended as are the other works.