Players Guide 2 introduces a the Crafting (Dexterity) and Poison Lore (Cunning) focuses and the corresponding talents Trap-Making and Poison-Making, as well as a new background Ferelden Craftsman.
Players Guide 3 introduces the Enchantment (Cunning) focus and Runecrafting talent. Runecrafting is not, however, for making new items - it just allows you to mount runes onto existing weapons and armour.
Gamemasters Guide 3 has the rules for runes, but about their creation it only says, "Skilled dwarven crafstmen and the Tranquil know the secrets of runecraft."
So, unless it was added in the combined books (which I don't have) there is nothing in the rules about playing Sandal Feddic. Enchantment!
As an aside, playing an enchanter would probably prove to be really boring.
GM: OK, so Alistair and Leliana finish off the fleeing warriors while Morrigan (who disapproves -20) uses the last of her magic to make sure the abomination stays dead. Sandal, what are you doing?
Player: Continue working in my lab, I guess.