There are usually a handful of sorcerers in any given nation, a bit like there are a handful of top-tier rocket scientists, and they tend to be employed by governments directly, receiving hazard pay for any actual spellcasting requested of them. Various high profile spells-gone-wrong cases are known in the public (often somewhat deliberately), which helps dissuade interest in the profession.

Still, inevitably, there is a black market for sorcerers, and some hardcode hobbyists also fall into the topic, although the latter will have a very hard time getting at the necessary raw materials. (Reliable access to high-efficiency local anaesthetics or nerve blockers is also recommended.)

At time of play, most active legal sorcerers (~50 or so) are on Mars to help in making it habitable, with only a small handful back on Earth (~5 or so, likely one per political ‘super power’).

There aren’t any notable amount of illegal sorcerers (that haven’t already messed themselves up beyond the ability to spellcast), maybe 5 imprisoned and another 5 free, all unaffiliated with each other. The ones that are free use their powers almost exclusively for alchemic transmutations of substances, and they aren’t likely to be active at a significantly higher rate than legal sorcerers.

99% of a legal sorcerer’s work is to find new spells from theoretical groundwork, since those found through archeology are only going to get humanity that far, which is mentally challenging work that computers can only help so much with (but are nonetheless essential to – think protein folding, you don’t ever want to have to do that by hand). High-tier spells are usually pretty obvious once discovered and are informationally quarantined more or less immediately.

Illegal sorcerers usually don’t bother with tedious research, but in theory, there’s nothing stopping them.