I have recently purchased a 99 mustang and have found that my radiator cooling fan does not turn on, upon further investigation I have also found that I get no power to the fan, and I also tested for power through the CB fuse in the fusebox and I don't have any voltage running through that with the A/C on either, what could be causing this?

 

Without checking myself, I would suspect there are cooling fan relays.
If you look in your owner's manual , you should find a diagram showing the number and location.
Power needs to be verified at the switch and getting to the relay when requested. If power and ground are present when required, isolate the fan from the circuit and supply power directly to the fan, that will tell you if it is in working condition.