Norma, even though this is an old topic, following your journey using the two Italian cultures I just ordered from
www.sourdo.com is invaluable because I also have never done a starter/poolish before. I ordered the "Classic Sourdoughs" book, but the process is a lot clear to me after reading this thread. Thanks for starting it, and everyone's posts.
I sort of jumped off the 'Varasano Bridge' after reading and
printing out a copy of Jeff's website, and cutting off the Whirlpool Oven Self-Cleaning locking latch with my Dremel a few days ago. I get up to 850°F on the stone within 35 mins; 1000°F at top. Kind of scary cooking a pizza in 2mins, and burning it in 3 mins!

Jeff is right that the temps surrounding and in cabinet above the oven never went above 87°F. With only two pizzas down, many lessons being learned.