As of patch 2.4 blacksmiths are not able to make shields. If you decide to blacksmith you can make weapons and armor for your warrior but it's likely that you will find that the items you can make will not be as good as the quest reward or instance gear and weapons you get. So while it sounds great to make a blacksmith because it can make gear that you can wear and weapons you can equip it's really unlikely that you will actually use much of the items you create while leveling up your blacksmithing while you are leveling up your character. Best way to pick a profession is to look at the end items you can make because you will level fast and not use much of the crafted stuff while you level your character.