Namibia offers a variety of opportunities for tourism. You also may want to venture out–Cape Town and Victoria’s Falls are both in reach (although Vic Falls will be an adventure no matter which way you go).
Start by checking out what information is online. You might also want to check out a Lonely Planet book for Southern Africa (like this one or this one or this one).
A great resource my Mom found is the Card Board Box Travel Shop.
More to come…