Brock is a blacksmith in Bavelock and the owner of Fire and Steel. The first time you meet him he is busy working on a special sword and won't talk to you.

Only if you complete the sidequest "Helping Jaden" he will talk to you and will be able to offer his services as a blacksmith.

In "Helping Jaden", Brock tells you that he is working on a sword and might finally be ready to show it to the swordmaster Argas, if he likes the sword then Brock is satisfied. You are given the sword and show Argas it. You enter battle and simply hit him with the sword one time.

Once you have shown the sword to him, Argas asks to see it in a real battle. So Luvannon summons a Gornak for you to fight. After the battle you talk to Brock who thanks you, and then talk to Jaden again who gives you 25 Pix for the help.