So I read the comments you guys left me (shoutout to Ana and Chelsie)
SICK SOURCE GAME ENGAGED
African Hip-Hop Web Exposure - This one is awesome. It pointed me to africanhiphop.com, which is basically a live feed of exactly what I'm researching. The guy who runs it seems really cool, too - I might try and hit him up for an interview via email.
The Hip-Hop Generation - This will sprinkle some social awareness in here. Evaluating music in its own right is all well and good, but to understand it I need to know the environment it was created in.
African Underground Vol. 1: Hip Hop Senegal - Unorthodox as a scholarly source, I know - but this topic calls for hands-on research. Limited to the Senegalese scene, sadly, but it appears to be a vibrant one.
Power of Unity This 2000 Pan-African Movement hip-hop compilation is probably the strongest primary source I've found. Also tenuous as a scholarly source, but too good to pass up. I've already requested it, so hands off.
The Hiplife In Ghana - Interesting in its promise of an evaluation of the hip-hop culture that tends to be inseparable from the music itself - here I can research all the ancillary bits of African hip-hop and how they (break boys and DJs, particularly) used the new forms to showcase what they already had.
Bundle up.