Surely the guy at the A/C place could have checked the fuses for you, he must have a chart detailing where all the fuses are.
Anyway, there are two fuses to check for your system.
In the fuse box under the steering wheel, the fuse for the A/C system is fuse 14, it should be a 7.5amp fuse.
In the engine bay there are two fuse boxes, the fuses for the A/C are in the fuse box just under the windscreen on the passenger side. The one you want is fuse 12 which will be 20amp.
There are also two relays behind the nearside (passenger side) headlamp. One is for the clutch on the A/C compressor, and the other is for the condenser blower motor, there's no way you can really check them without any electrical knowledge, but just make sure they're plugged in.
If you had the work done under your insurance policy the repairers should have made sure the A/C system worked. There's always a strong possibility that something in the system other than the condenser might have been damaged and lost all your gas.