the fuse for the aircon isnt in the main engine bay, they are only the fuel pump and ignition fuses, the three relays however are two brown one purple, one of the brown ones, iirc is the one on the left end of the line, is the aircon relay, if your aircon isnt kicking in then its more likly to be empty then anything like a fuse, there is a saftey feature where they dont click in when the pressure is to low.
if you are still looking for the fuses they are in the panel on the side of the dash by the passanger, open the door and they are on the end of the dash.
if that still dont fix it try replacing the relay... for some reason when i got mine someone had removed the relay completly so for £2 out of the scrappy its a cheap part