I finally have a phone; feel free to call any time.
Angola is effectively 5 hours ahead of the Eastern Time Zone in the US, but since Angola doesn't observe daylight savings this will change to 6 hours ahead of Eastern Time when the clocks change in the US in the fall. Think of it as the same time as London for now, and the same time as central Europe in the winter.
Number: +244 912 641 341
The first three numbers are the country code for Angola, so before that I think you have to dial 011 if calling from the states. Most of you know this already, but just in case...