Honestly, if you are not super large chested, I would look for some soft cup regular bras with enough stretch to them that you can just pull down the top of the cup, and then get a few nursing tanks.
I saw this one at the store today, and thought it looked super comfy, and it was nice and stretchy!
Warner
I love my Bravado nursing tanks, and think this bra by them looks really pretty! Considering purchasing it when I have the money...
Bravado Sublime Nursing Bra - Best Price
I like that the Bravado bras and tanks have a full clip down, instead of the little hole cut-out on the interior layer.
P.S. I definitely had no desire AT ALL to wear an underwire in the beginning, but once bf-ing was well established and I wasn't nursing every 45 minutes, the underwire bras were not a problem for me. It is most crucial in the beginning when your milk supply is regulating and you are dealing with engorgement to have comfy bras. After your supply regulates, you don't have to worry as much about blocked ducts.