I have to second what Don and plastic junkie have to say about Aclad. There’s just no beating it. They have a site up but it’s nothing fancy. It will provide you what you need to get started. I would tell you that for your build you need only really get 3 or 4 shades to accomplish what you’re looking for in a B-17. You’ll be better off testing it on something before getting started on your actual build so that you have a feel for how it will respond. You’re Revell 1:48 B-17 will work out just fine too. I have one myself but it’s been put on pause. A few after market parts will take it a long way to help it out. True Details can fix you up if the Eduard stuff seems to fidgety. Quickboost has some engine replacements too if it matters. Here are a few sites to reference to help you get started with Alclad:
http://www.swannysmodels.com/Alclad.html
http://cs.finescale.com/fsm/modeling_subjects/f/2/t/151736.aspx?sort=ASC&pi240=1
http://cs.finescale.com/fsm/modeling_subjects/f/2/t/155345.aspx
http://cs.finescale.com/fsm/modeling_subjects/f/2/t/157735.aspx
Hope that helps!! =]