I'm with the others, use the Ragbrai routes. At least the second half of this years will be close to perfect for you.
Also has anyone noticed the recent increase in threads relating to Iowa 3 in the last week. can't say that I mind though.
After REALLY working hard all winter to stay fit I'm looking forward to Ragbrai. I'm pedaling from my house in Clinton, overnighting near Cedar Rapids, and then staging the next day into Marengo so that I can ride the last 2 legs of RAGBRAI to the river before turning the old tourer north to home.