Your clan will have in a person from a clan that they deal with in these matters, who will look over your loot and then offer you a fair price for them. They will then turn around and find buyers for the loot, and sell it to them for whatever profit that they can make.
There is a sort of 'black market', but it's mostly to evade Imperial taxes - which is probably the leading sport in Tsolyanu. Keep in mind that anything and everything is available, for a price; what everybody wants to do is keep the Imperium from getting involved and getting their sticky fingers in the money pouch.
As for 'organized crime', keep in mind that a lot of the things we'd call crime these days is considered normal business activity in the Five Empires. (It's much worse in places like Haida Pakalla.) About the only real 'crime' is treason and rebellion, which is sure to get the unwelcome attentions of the Imperium. (There are all sorts of people working behind the scenes, too. The OAL, for example.)
(Murder and violent crimes are a different story; the perpetrators usually are found dead in short order, after their subject's clan finds them.)
Now, 'income tax evasion', 'not paying customs dues', and similar things are what really constitutes the 'black market', just as it did in Colonial America. The Founding Fathers were annoyed with the British East India Company for importing tea and selling it for less then they could make by smuggling it into the colonies. So, in the best 'organized crime' style, they hired dear old Harchar and his "honest seafaring merchants" to dress up in costume and toss the goods into the drink.
There is very little traffic in 'ordinary hot goods'; thieves certainly do exist, but there aren't any 'Thieves' Guilds' in the Five Empires. (Some would say that they are called 'tax collectors', however.) If, say, you wanted something stolen, you'd contact the clan that handles such things; same thing with smuggling. If you want something done - as the Russians say, "on the left" - then you contact the clans that handles such things in your town. The best place to start looking for them is always the Market Police or Customs and Excise officers. They'll put you in touch with who you need to speak to - for a small fee, of course. The smuggler clan will then make sure that they get a donation to their old age, pension, and retirement funds, and everybody is happy.
Avanthar might get cranky, but, well, that's the way things work. As an Imperial Governor, I had several occasions where I made sure to look the other way, as it was the only way to keep the Imperium running. As long as people kept it down to the customary levels, and nobody got hurt or any riots or rebellions got started, things were fine. When people got stupid, that's when I'd have to pay them a little visit. My little galley's crew are all 'retired' smugglers, for example, and I make sure to 'suggest' to the Customs and Excise officers that they really don't need to look in the luggage bins. (Rubs thumb and forefinger together, in the ancient gesture.)
What?
Arrest Harchar and his merry crew? Are you
nuts? Think of all that
paperwork!!!
Does this help?
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