This is the place to go if you want to find a bra which truly fits, especially in harder to find sizes. They'll also track what you've bought in the past and keep your preferences on file.
Go in when you have time to do a proper fitting, even if you're not ready to buy that day. Also worth trying on any other styles (such as sports bras) which you might want while you're at it.
Their prices are high - bras range from about $70 to $200+. This is partly the higher-end brands they stock, though their prices tend to be high even for the specific brands.