Moonshine is legal, so anyone can buy a distillery in any decent store (usually sold with small agricultural equipment), from 10 liter to 200 liter ones. Many people choose to make their own brandy, out of their own fruit, or what they buy on the green market or directly from peasants. There are also destilleries where you can bring your fruit and have it distilled, or do it yourself.
In Serbia proper it's usually grape or plum (lozovača, šljivovica); in Vojvodina, any fruit, with quince, apricot, pear and apple ranking higher. During the crazy year of 1993, when astronomic inflation rendered any prices pointless, the German mark was the real currency; regular loza sold for 4 DEM while quince went for 13 DEM and nobody ever complained about the price.
Pretty much anyone is a connoisseur of brandy. Real connoiseur doesn't buy brandy from a supermarket, he knows the man who doesn't really mass-produce, just makes a few hundred liters for himself and sells the surplus to friends only :). While this sounds like a joke, it has some truth to it - there is a lot of knowledge involved, and the brandy may often turn out bad, or cause a headache, or stink, or be sour etc etc. There are those who add sugar to increase the alcohol content; some percentage is legal, but overdoing it may cause bad fermentation and you can even get methanol. The last few guys who did (and were caught after customers started dying or going blind) that are still in prison - and this was not even moonshine, they were regular manufacturers.
The simple test (so you can pretend to be in the know): bad brandy burns your mouth; decent one burns your throat; good one warms you between your lungs.
Another simple test: wet your palms, around the root of your thumbs, with a few drops of the brandy you're testing. Rub them vigorously against each other for a few seconds, to warm them up. Take them to your nose. You should smell the fruit it was made of, or at least it should smell nice. If it doesn't, your nose is numb and you need a shot to wake it up.