Rewiring a switch controlled receptacle to a ceiling fan
Based on your description, it sounds like your wiring is this.



To wire the fan, you will need to remove the switched loop and convert it to a regular wire.  So in the outlet box, disconnect the neutrals and hots.  Wire cap all 3 neutrals together with a pig tail to reconnect the outlet, do the same for the hots.  At the switch, remove the neutral from the switch and wire cap that with the neutral to the light.  Then put the hot to the light where the neutral was on the switch.  Like so.

  

I did not add grounds in the picture but they should be wire capped together in each box with a ground wire to the outlet and switch.