Body pillow is about my only need right now. Mine is a cheap-o one from Target.
You'll eventually need bigger bras, and cotton sleep bras can be helpful at night (more comfy than real ones, but provide some support).
I'm about to move into maternity jeans as soon as I dig them out of the garage. You'll need longer shirts to cover the gap if you wear lower-rise pants, or some women use the belly bands for that purpose.
Definitely start looking into what type of birth you want - if you want to take classes, some courses are pretty lengthy. Read some books about birth (from different perspectives, since a lot of them are biased). Read books about infant sleep habits, breastfeeding, and whatever else you can think of - it's better to be knowledgeable before LO arrives.
Also - work out a budget. Diapers get really expensive. Formula (if you choose to FF) is very expensive. It's good to have an idea of what those are going to cost you. And that's just the beginning. Despite their small size, babies are pretty expensive