What's Your System For Searching For Errors/Varieties?

Separate everything by year and then go through each year using variety vista/wexlers die varieties for reference. I pretty much hunt for everything.

Good advice above and sounds like you are on the right track.

The only thing I would add is: Know what you want to look for [specialize] - It is very time-consuming to try and look for everything.

Dearborn, you have here the previous answers which put you on the good track.

Me I wrote to you from the point of view of a collector, not like those who answer you who are specialists. Is no software errors recognition. Around you find many studies and sites who mention mint errors. Some say error, some say variety. Except post mint strike, in collecting we say errors. Variety are different die retouch or design (this is the ways the collectors look). The specialists who look those any minute have maybe different opinion, but bottom of the line will be same.

A good magnifier 20-40x 20$ (goldsmith) is ok. But I will opt for a decent approx. 100$ microscope with 7 inch screen which have camera. This will be a good depart.

Good luck

All of the above are excellent ideas.
The thing I'm going to advise is something, as a collector, you may have already done.
Assimilate a reference collection of normal coins of the type , dates and mints you intend to search. As you begin to investigate the fine details of each coin and think you might have found a die anomaly, this reference collection will be the learning tool you use to determine if a coin warrants further investigation.