It worked this time. I let the starter sit for 4 days. The only problem was that I made the dough too loose and had to bake it in a bread pan. It takes a lot longer to rise without yeast, practically all day.

I don't have a picture because it's almost gone. The texture is crusty like french bread and it does have a distinct sour taste.

I have my base started for the next time, and I think I'll do what Dak suggested and use yeast with the sponge to move things along quicker. At least I know that I don't need yeast to make bread, but it sure takes a lot longer.