
Do not forget to make the pleasant climb up Kgale Hill, one of Botswana's largest hills (at about 100m). It provides a magnificent view over the city and surrounding areas. Be careful of the baboons, though, and do not stray off the path. There are no guides, and there is no entrance fee to worry about. theres lots of stuff to do here!! ;)
Customs is very slow, but easy to get through (as I assume is the case for most of Africa). Have an address on hand for where you will be staying and they hardly give you a hassle. If you are worried about customs, a useful place to visit is the Botswana Embassy in Washington, DC.