Blowing CTSY fuses

Problem: Horn, door locks, cigarette lighter, glove box and dome light do not work. I changed fuse, it lasted long enough for me to test the power door locks and then it blew (locks did work). As soon as I installed another fuse it blew. I know I have a short somewhere (bad ground), but where would be the best part to start? According to my aftermarket manual, I can test the circuit with the fuse removed...how do I do that..I am concerned that I might start a electrical fire. This is my first vette and have the fever! Thanks in advance!

Feltman, I don't know if you saw my reply to this before it was lost out in "cyber space," so I will try again.
First...what year is your car? If the fuse blows as soon as you hit the power lock switch, you most likely have a hot wire touching metal or another wire. Check the wires from the lock actuator in the door all the way into the car. Make sure that no door panel screws pierced through the wire harness, and check where the wires pass through the door into the car. Those wires are constantly being flexed every time you open and close the door. Last, it may be possible that the power lock actuator is shorting out. Compare the resistance (ohms) between the drivers side and passenger side actuators.
Good luck, and keep us posted.
Sarge