I am unsure how old the Fridge is. Condenser works. Will not get cold. I did not feel any air coming out of vents in the freezer or fridge so I checked the Evaporator Fan. Not turning, but spins freely.

I tested by hooking up old plug to wires and fan turns on. I checked the voltage coming to the fan and Hot to common is 77v.

Per forums, thermostat could be the problem as it is pigged in. I tested the resistance by putting in ice water and checking, but not showing value. I bought a new one and getting the same reading of nothing and plugged it in anyway, but the fan is still not working. I guess the way I was testing was wrong as what are the chances of a brand new thermostat being bad? I put on 200 ohms and touched the test contacts (1 brown & 1 orange wire) and multimeter read 1, the same as when not touching anything. When I touch the leads together I get reading.

I am not sure what to check. It is for a friend who is strapped and I am staying with them (jobless) trying to help them out, I'm not an electrician either. I don't want to waste more of their money to buy parts they don't need.

I was going to try to trace all the wires to look for burnt out/disconnected/broken signs but it is in a tight spot to work on (have to keep pushing all the way back to go into the front and jumping over counters and vice-versa) and am not too proud to ask for help. So.... please help.

I read about the main board but it is no longer made. Very difficult to find another.

Maybe I am overlooking something obvious.

Here are your parts
Replacement parts for SPD25QA3L models | AppliancePartsPros.com

See the attachment for a tech sheet. It is the closest I could find and is for SRD25T but with luck yours will be close.

If I then click on the picture of the defrost control another page opens with info on what units this part is also used on a SRD25TPS so it may be the closest match.
Note That there are other units in this series that use it.
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Condenser works. [/COLOR]
By condenser I am assuming you mean the compressor. You can usually hear it but it should be warm and you should be able to eel it vibrating.
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I tested the resistance by putting in ice water and checking, but not showing value. I bought a new one and getting the same reading of nothing and plugged it in anyway, but the fan is still not working. I guess the way I was testing was wrong as what are the chances of a brand new thermostat being bad?[/COLOR]
It is not a good idea to immerse these in water. If water gets into it the thermostat will be toast.
Looks like the thermostat closes at 25 degrees F so the water would not be cold enough. Hold the face of it on an ice cube.
Getting a bad replacement part is always a possibility.

When you removed the evaporator /freezer cover to check the fan what did the evaporator coils look like?
If the compressor is running and there is no frost or just frost in one area on the evaporator coils then you have a sealed system problem.
Note that the compressor has to have run for an hour or so because if you do this shortly after a defrost cycle you will end up with the wrong diagnosis.