The trader, Haldor, can be found in the Black Forest, with a little searching. The trader is useful to purchase a small number of items currently, although it is fully expected that more items are added to the trader as the game is developed further. At the moment this is the only place to obtain a fishing rod and bait, and a very useful increase to your carrying capacity of 150kg, Megingjord.
Other useful items are the Ymir Flesh, which is essential for crafting a powerful hammer, and the Dverger Circlet, which provides light wherever you look. None of these items can be found elsewhere, however it isn’t essential to progress in the game if you don’t have them, so don’t worry too much if you can’t find him.
The truth is, Haldor can be tricky to find. He may spawn many islands away from your location, and he may be in an inhospitable position. The only consolation is that your map lends you some assistance. If you step within 690m of his location (quite a distance) then a moneybag icon will appear on your map. If you see this the rejoice, for you have discovered his location. It will be within a black forest biome.
Once you’ve found Haldor, you can approach without concern. Speak to him to see what he has for sale, and for how much. The currency in use is gold coins, usually obtainable from killing trolls or hunting in burial chambers for it. You can also sell valuable objects, such as amber, rubies, or pearls for more coins. For the Megingjord, which we advise is your first purchase, you will need 950 coins. A ruby will fetch you 20 coins, amber will bring in just 5 coins, and amber pearls 10 coins.