Have a good look through the countries you will be travelling through on this site, there`s a lot of info available, check the latest travel advices from the foreign offices linked on this site, subscribe to the Africa Guides newsletter, and finally post a message here (oh you already did that), don`t forget to post specific country questions in those forums if you have any.
Also get some good guide books.
Planning is the best insurance..
Phil j
moderator