Serious Eats - seriouseats.com

You can dump the starter into any yeast bread you make, you just need to account for the extra flour and water you're adding, if you're using precise measurements. But if you eyeball it, you can just toss it in and adust basd on how it looks and feels. You can add yeast so it rises faster like a regular bread dough with a little sourdough flavor, or that can be a sourdough loaf, if you've got the time.

Or, you can adjust the way you feed your sourdough so that you don't end up with all that extra. I've got three different strains of sourdough in my fridge, and I just save a little bit; there's maybe a quarter of a cup in each jar. When I'm ready to make sourdough bread, I start feeding, approximately doubling it each time, until I've got enough starter to work with. I leave pretty much whatever is clinging to the jar, add just a little water and enough flour more to make a fairly stiff dough, and pop it in the fridge until the next time I want to make sourdough bread..

Read "Bread Alone", it will change your bread making life forever.