The problem originated with lukewarm fridge, noticed the plastic coil in freezer completely iced over, so, I defrosted the unit. One week later, same occurrence , once again defrosted unit . Now freezer,nor,fridge producing cold tempetures at all. Turned unit off for one week, ultimately concluding fans working, however, there's a noticeable clicking sound coming from bottom backside off fridge (compressor?). The clicking occurs seemingly every 40-50 seconds,as though something isn't able to start. I am a super handy woman on an " arctic" mission! Help !

Sounds like the thermal overload on the compressor is "snapping" on and off. First would be to check the switch by bypassing it for a minute or two. If compressor runs and cools, replace switch. If compressor doesn't run, lights dim or throws breaker, it's probably time for a refrigerator, compressor replacement costs about as much.

Where would this infamous switch be located?

Your problem is in the defrost system. If it is a normal type it has a defrost timer which turns off the fan in freezer and the compressor and energizes the defrost heater until the terminator t-stat turns it off or the timer turns it off, whichever one is first. It's a very straightforward system that is easy to work on. The electronic ones are totally different, but normally when they go bad only the heater and terminator needs to be replaced. Just remove the cover to coils in freezer to access heater and terminator. Don't forget to clean the coils under unit, too. Many times the timer is under the unit near the coils or near the t-stat in the refrigerator section. Let unit thoroughly defrost before working on it. After removing the cover to coils you will see wires leading to a heater attached to the coils. On a side-by-side the heater is a glass rod with an element inside that you can see if it is bad; on a freezer on top model it is aluminum and wrapped around the coil that will burn apart often. There is a defrost t-stat attached by wire to one side of the heater and clipped onto the coils. It is round and has two wires, one to the heater and one to the power from defrost timer. With refrigerator unplugged turn timer until you hear it click and stop. Have wires unplugged to defrost heater and defrost t-stat and get the plug and the wire supplying power to heater. Put meter on ohms and put one lead on wire supplying power to heater and one to plug prong and if timer is good you will read about zero on both prongs – one to each wire supplying heater power. Then put one lead on each side of heater and if you have no continuity you need a new heater. Replace heater and terminator together and be very careful when replacing it, especially on the freezer on top model because if you bend the wrong thing you will break one of the delicate capillary tubes and lose all of the Freon which will ruin the unit. If the timer is bad you will need to replace it with one that matches. You can test it before you take anything apart by advancing it until the refrigerator turns off. Then see if the heater defrosts the unit and then brings the unit back on; if it does not then all you may need is a new timer. Make sure to test the fan in the freezer, too. If the refrigerator has a defrost problem too long it will cause liquid refrigerant to flood back to compressor washing the oil off the walls of the cylinder and ruining the valves and scoring the cylinder walls which causes the compressor to lock up. This means the compressor will not run unless you install a hard start kit, which will give the compressor motor enough torque to start. If you are hearing clicking and the compressor will not run then it is locked up and a hard start kit may get it going again, but the defrost system has to be fixed or it will ruin it.

Look on the side of the compressor, should be little box or part with 2 wires. Also make sure the fan is working and all dust removed from compressor area. Try to start the Refrig and see if you can find the part by the clicking noise. You go girl!

If you find that the compressor will not start and the sound of clicking is coming from the box on the side of the compressor then unplug the refrigerator, first. Then get a good digital volt/ohm meter from Radio Shack or somewhere else. Remove the cover on the box on the side of the refrigerator. On the inside you will see a relay plugged onto the two bottom terminals, usually, and an overload plugged onto top terminal. Unplug all of this and there will be three metal posts. With your meter on "ohms" read from each post to a copper line coming out of compressor. Any metal that will conduct to the outside shell of the compressor will work. If any of these give you a reading then the compressor is grounded and therefore bad. If it passes this test then read between the three terminals. Draw a diagram. Read from top to bottom left and top to bottom right and between two on bottom. The three terminals are Common, Start, and Run (or Motor). From Common to Run will be the lowest reading; the top terminal will be Common on most units. Common to Start will be second highest, and Start to Run will be the highest. An example: Top terminal to bottom left = 8 ohms, Top terminal to bottom right = 6 ohms, and between two bottom terminals = 14 ohms (8+6=14). So, we would know that the bottom left is start and the bottom right is run, top is common. When you buy a hard start kit with start capacitor you will need to know which terminal is which so you can install it.