rparker, at the end of my first pregnancy I was advised to get something stretchy, like a sports bra, so I could have the needed support (and something to hold a breastpad) yet it would adjust to fit me as my size fluctuated.
Then about 2 months post partum, I measured and ordered nursing bras online, and they lasted me a long time. I also loved the Gilligan & O'Malley nursing tanks from Target, but I understand they don't work well for REALLY large sizes (I ranged from a 32 B to a 36D, and I found them very ideal).
After DS self-weaned in January, I went out and bought myself a few nice bras for about $15 a piece at a department store during a sale. I wanted something a little more flattering and un-nursy.
And yeah, my toddler didn't care if my bra was the regular kind and I just kinda lifted my breast up and tucked the cup under to support it like a shelf.