For Africa, make sure you get maps sorted before you go. Having gotten them on the hoof in other parts of the world we didn't, and regretted it as we ended up relying on the good will of other travellers en route to sort how we were getting to where we wanted to go! We managed to pick up maps in The Gambia, but they were more expensive then UK and less choice. For our next trip down the east coast we were hoping to obtain Asian maps and guidebooks from Sth Africa, only to have a SA friend tell me that this is not a good idea, and to get them before we go or have them posted en route.
Hope you have a fantastic trip!