I'm a 36D/38C and have had trouble finding a good sport bra, too, at least until lately. I get real tired of the una-boob approach, and there are a few bras out there that take a different (a la lift-and-separate)..angle, as it were: The Moving Comfort "Maia" and "Mesh Underwire" bras are good (I found them at SeeJaneRunSports.com). As is the Champion Shape T-Back Sports Bra (you can find it at Champion's web site).

Good luck!