lian-li's PC-V1100plusII is very quiet, available for about $250.
the p180 would be good as well, being a big steel case, you could quiet it down pretty well.
if you want to try to quiet down a case you already have use the acoustic foam, or install some dynamat on the side panels, some cases have rubber or silicone gaskets to dampen vibration from hard drives, but if you already have a way of dampening the vibration on the side panels, it won't make much of a difference, as the vibrations won't resonate within the case.
and get good fans, you can go crazy with expensive fans but I've found that these are the best, considering price, provided the case will accomodate 120mm fans.
a fan controller will help too, most install in a 5 1/2" drive bay, they're convenient but often clash with the styling of the case, I like the zalman fanmate 2, it's cheap, you buy one for each fan, stick them to the inside of the case, adjust them to your liking and forget them.
if your case has a metal door, all the better, just put some rubber around the edge and it can have a dramatic effect compared to a case without a door, especially with a cd fully spun up.