Cacique at Lane Bryant or Helen of Troy. I'm a 40GG, and I love both brands!
I'm in a 49/42 DD right now a week post partum. I've been wearing the Giligan & omalley brand from target with a bra extender. I don't like the number sizes, but the letter (s,m,l,XL) are more comfy. I'm in an XL. Plus they are super easy to unclip one handed for nursing.
Wacoal is a great brand! I'm size 36G and that's the only brand I buy.