Umbra, as you may have gathered, does not make friends easily. However, we do have trading partners. Our primary partners are Jhelom and Nujel'm; we also trade with Zento; Minoc; Moonglow (although they would prefer that we didn't); and we have a secret relationship with Wind that they would prefer we not make public. (Wind is a strange place.)
Our primary imports are thus:
Crops - all sorts. We have trouble sustaining our population and must rely on our trade partners to keep us going. Before the links to Britannia opened up, we had to survive by stealing sheep from Luna; it was a sad situation.
Fruit - especially tropical fruit. Mangoes and passionfruit are a craze right now. No peaches; one of our senators has a phobia.
Beef and Gaman Meat - our climate is not good for bovines.
Zoogi Fungus
Ceramics - from Zento; they're very popular with the nobility.
Wood
Animal blood - any animal. Jhelom are most obliging.
Furs and Skins - brown bear fur from the forest and polar bear fleece from Dagger Isle, both of which we get through Moonglow. Nujel'm send us snakeskins.
Daemon Blood - from Wind.
Dead Dragons - also from Wind.
Gold
And our primary exports are thus:
Salt - salt from the Gravewater lake has a distinct rosy colour and a delicate, slightly sweet taste. It preserves just as well as regular salt, without overwhelming the flavour of the meat.
Fish - there are fish in the Gravewater lake, and they are proof that there is a God and he is a madman.
Nightmares - yes, there are brave men out there that breed nightmares. Hand-reared foals are extremely expensive, but they are in high demand.
Silk - grown naturally in the caves around the Gravewater desert, which is Umbrian land.
Cochineal - we do so love the colour red.
Sand - we export sand to Wind. No, I don't know what they do with it.
Lindaes
Crops - predominantly corn and potatoes. Our farmland is not very good.
Goats, Sheep and Llamas - we produce a lot of goats down around Umbra. Sheep and llama farms are a flourishing industry in our foothills.
Petrified Wood - Vast sections of the corrupted forest are petrified, a phenomenon rarely seen in Britannia. We primarily export this to Jhelom, where it is popular for peasant housing due to not rotting in the tropical climate.
Reagents - necromantic, predominantly; there are vast seams of nox crystal beneath the desert, and every rainfall washes away earth and uncovers another layer of fossilised black pearls.
Constructs - demand is higher than you would think.