I have had 3 phone calls over this just this week.
I order my diapers from amazon.com. I get 1 case (Size 4 64 diapers) of Overnight Diapers shipped to my house for $13.84. I also get a box of Snug and dry (Size 4 140 count) for $23.45. If you get use Subscribe and Save then you get 30% off your diapers, they are delivered automatically and you get free shipping from Amazon Mom.
If you want to do this go here http://www.amazon.com/gp/mom/signup/welcome and sign up.
Next select what brand you want and they will be at your house within 2 days. I love this program because if I need more diapers, I go to my account and schedule a new delivery. I can also skip shipments if I need. Even though I am a coupon crazy maniac, I still find this is cheaper in most cases.
Also I use Swagbucks as my search engine for everything. Every 450 swagbucks I receive by searching, I cash in for a $5 amazon card to use on diapers. If I go to look at any website, yahoo, facebook, etc, I use the search engine to look for it to get more swagbucks. Go here http://www.swagbucks.com/refer/mamachelle and sign up.