snoopea has pretty much everything covered.

It might pay to buy a pack of terry toweling nappies to use while feeding bub, in case he/she has a little spew.
Buy cheap undies for after the birth. You bleed quite heavy, and you'll probably just chuck them out anyway. Preferably dark ones.
Definitely stock up on the nipple cream in case of cracked nipples, and plenty of breast pads just in case.
You can never have enough wraps.
Good idea about buying next size up nappies.