Cooking as much as I do, it seems downright silly that I haven't yet used a cast iron skillet. I'm looking to get one, and a dutch oven here soon. I've done some preliminary shopping, and see there's obviously a wide range of choices and prices. Not knowing the first thing about them, I don't even know what to narrow down to. Obviously, the most expensive options like the Le Creuset skillets aren't going to be what I'm after. But what separates the $20 skillet from the $100 skillet?