The essential MUST have items, especially if you ahve a newborn and need tons of diapers, go on Amazon.com, sign up for Amazon Mom & subscribe & save on items. savings are great. obviosly you won't need the monthly supply of the same size diaper, so, cancel at any time without any problems & subscribe for another size! I just did and it was GREAT!
I think this is also useful for day care centers that use certain items on daily basis, unless they get some other kind of dicount with big stores and stuff. :)