HI helpmeat~
We all want to look our best reguardless of what size we are. And because the cup size of your breasts are a DD, you wont be able to get the kind of lift that someone of the cup size, of say a size C cup would be able to get, but there are some manufacturers of bras out there that are better than others. I can speak from my own personal experience, I am a DD cup too and I have always shopped in the Lane Bryant catalogue for a good supportive bra. I go for a brand called The Goddess bra. It doesnt have underwire that pokes you in the side and there are two models of the Goddess. oOne has stays on the side, this is the model I wear bc I like how the bra holds me in on the sides. A new bra of course gives much better support, and bras should be thrown away very often. The elasticity wears out. Straps help with more support but dont need to be thick and ugly. the betterthe straps are the less back strain you will get, and the more you will be pleased with your appearance. What I would suggest is to go to a department store, to a lingerie dept and ask to be measured properly for a bra. After you have the proper measurments, look up either Lane Bryant or another company (or a lingerie manufacturer) on the web and order accordingly. You can always consult with someone over the phone , and if the store is in your area you can go in and try it on to see if you like what your getting. DOnt forget mail order catalogues have a return policy. 
I wish you the best of luck.
