I've been using a sourdough starter exclusively for baking for the last 3 or 4 years. Before yeast was commercially available this was how everyone did it (using natural preferments). I've found that it's possible to use a starter as the leavening for nearly any purpose with comparable (or superior) taste, quality, and texture that you would get using instant yeast. From baguettes to panettone to chocolate cake and scones, sourdough isn't about a certain taste, like we know from San Francisco style sourdough bread. Instead, it is a method used to provide leavening, and it has been used successfully in all the aforementioned baked goods. I've also found that there are a lot of misconceptions about sourdough starters and their use. Even well-known, well-respected, and quite accomplished individuals (bakers and chefs who enjoy some measure of notoriety--and deservedly so) pass on things that are based on what they've decided is true after sorting through all the conflicting information. And I can tell you first-hand, this makes it very difficult for anyone interested in using 100% sourdough starter exclusively for baking!
My pizza-making history goes back a long way. When I was growing up, my father decided that Mom should have Sunday's off from cooking. He would make pancakes every Sunday morning and my older brother and I would usually make pizza for lunch. Of course, back then it was Chef Boyardee out of the yellow box. It came with a packet of flour and a can of pizza sauce. You added water to the flour and spread it out on a pan then dumped on the sauce and added toppings. It was very far from world-class pizza, but it was fun to be the chef, and it satisfied us, though I suspect that's mainly because none of us had ever had the chance to eat world-class pizza, and you can't miss what you've never had.
I mainly used the sourdough starter for scones, pancakes, and waffles when I first got it started. Occasionally, I'd try my hand at a loaf of bread. But I found I was the only one eating what I'd made. It's just my daughter and I, and sometimes she would try the pancakes or some of the bread, but I could never count on it. I decided that if I was going to have to eat all of what I made, I would prefer to learn to make world-class pizza--something I definitely don't get tired of eating! Pizzamaking.com has been a great resource in this endeavor, and now that I've developed a certain measure of experience and skill, I find myself wanting to contribute a little to the forum myself. It's my hope that people will come to realize the versatility of sourdough starters, and that those who are looking to learn will find information based on real-life experience, and well-conducted, well-documented tests.