I have a 1984 Catalina 30.
On my boat there is a toggle switch on the left side of the navigation table that is labeled AC Main (I think). Make sure that it is on (left)
Next, check that you have power at the AC outlets in your boat.. (V berth, head, galley, and port and starboard outboard of the settees... If you haven't got power there, then it's unlikely that you have power to a battery charger.
Perhaps one of your outlets has a GFCI (with the test / reset buttons ) which has tripped. You could reset them, or perhaps there is something wrong with the power at the dock. (Is the breaker on?)
On my boat, the charger is in the starboard locker, just aft of the wet locker.
A quick check to see if the charger is working is to turn on one of your cabin lights. Cycle your AC Main switch and see if your lights get brighter/dimmer... If so, the charger is working.
No dumb questions here... I like my Catalina 30 and expect you will too. You can get more information directly related to the boat at www.catalina30.com