I hear adding a bit of rhubarb to your sour dough starter for the first week can help. I've not tried it yet. Personally, I'd rather not add anything to mine. I'd rather not taint my bread with rhubarb
As for pizza bases, I probably wouldn't use a sour dough recipe. Sour doughs benefit from the over night sponge method of baking. That means you'd have to start making your pizzas the day before you wanted them. I just use dried, fast acting yeast in mine.
FWIW, nearly everything I know about bread came from http://www.amazon.co.uk/Bread-River-Cottage-Handbook-No/dp/074759533X/ref=sr_1_1?ie=UTF8&qid=1314395285&sr=8-1
It has a decent explanation of the whole process, but I think there is a type on the section on sour dough. can't remember what it is though.