Primarily the control wiring on a refrigerator is quite simple. The power comes in the power cord, runs through the thermostat and to the compressor. The fact that you are hearing a buzzing sound, followed by the breaker tripping is indicating the thermostat is working.
I would begin by pulling the cover off the compressor wiring terminals and inspect the wiring to see if a wire was knocked loose during transport.
If all the wiring looks ok pull the start relay off and using an ohm meter measure for continuity from the primary power input lead to the "Start" terminal on the relay. You should get a reading of zero ohms with the start relay in the upright position. Now turn the relay upside down and you should get a full continuity reading. If not you will need to replace the relay, but before replacing anything you should test the motor windings.
To test the motor winds first note that there are three prongs extending out of the compressor terminal block that are arainged in a triangle pattern. There should be a diagram on the terminal cover that will identify the terminals, but you can not always rely on that to be correct.
I would begin by taking a piece of paper and place three dots in the triangle pattern the same as the pins. Number the dots 1,2,& 3.
Using an ohm meter, measure the resistance from terminal #1 to terminal #2 and record the reading on your paper. Now measure #1 to #3 and record that reading. Finally, measure the resistance from #2 to #3.
Examine your paper, the highest reading will be from Start to Run, therefore the remaining terminal is the "Common terminal". I,E. If the highest ohm reading was from #1 to #2 then you should label terminal number #3 C for common.
The lowest reading will be the Start to common winding, Since we have already identified the common, then you can easily see the opposite end of the reading is the Start winding and should be labelled "S". The remaining terminal can now be identified as the "Run" Winding.
Now add the resistance readings from Start to common and from Run to common. The combined resistance should be roughly equal to the Start to Run resistance. If so, the compressor terminals are ok.
If they do not work out in the described manner, measure from the steel housing of the compressor to each terminal individually. You should get a reading of zero from each terminal. If you get a resistance reading from a terminal to the compressor housing can that is indicating the winding is internally shorted out and cannot be repaired.
If the electrical tests worked out ok and the compressor is still locking up when it tries to start it is normally indicating bad motor bearings or the compressor could be hydraulically locked up from compressor oil that got into the pistons while the fridge was laid down or oil may be blocking the capillary tube.
Laying a refrigerator on its side for transport can in some cases be a death sentence. Depending upon how it was laid there is a strong possibility that oil from the compressor crankcase could have settled into the capillary tube which will completely block the capillary tube.
With specialized equipment under some circumstances the capillary tubes can be cleaned, however it is a very involved process and it is generally considered that the labor cost would outweigh the value of the machine.