Hmmm, do a few dungeon runs, carry whatever you can, and sell it all. The best shop to use for selling armour/weapons you get is the blacksmith in Anvil. He has a maximum amount of gold per sale of 1200g, which is the highest in the whole game. If there is more loot than you can carry, I tend to work out what has the best money:weight ratio. When you get to higher levels, loot that costs more than about 1600g, you won't be able to sell for more than 1200g, unless you are high enough in mercantile to invest 500g in the shop, in which case it will be 1700g. So in this case, even if an item that is worth 5000g, is only double the weight of something that is worth 1800g, the wise option is still to take the lightest item.
There is no real easy way to get money except playing for a while. I recommend becoming grand champion in the arena, because this yields 2.5-3.5kg a week as you become better.