I just found out that my oranda had dropsy it dies this morning. The pet store said it was dropsy. Could anyone lead me to any info about this and what to do

Dropsy is when fluid builds up inside the fish, because an infection caused its kidneys to stop working. By the time you see the fish swollen with its scales sticking out, there isn't much you can do... by that time it's usually too late to treat them. A last ditch effort might include either medicated food, or shots to get the antibiotic into the fish's system and salt to help try and draw out fluids. A vet might also use steroids to reduce inflamation and a diuretic to help the fish excrete fluid.

Did you have a look at the treatment section yet? There is a section with available medications on top, while various diseases, their symptoms and available treatments are listed.
Here is the link to Emma's article on Dropsy.....
http://www.kokosgoldfish.com/forum/index.php?showtopic=12658

Dropsy by itself is not an illness, its rather a symptom of a few possible illnesses - some fish are sensitive to temperature swings, and a water change with slightly off temps causes them to dropsy. That kind is the easiest to cure. Then there are the illnesses like internal organ failure, like Betty mentioned above with the kidneys, as well as a few other posibilites.
The most important part is to treat as soon as possible, the sooner treatment starts the higher is the success rate.

And to prove that there is hope for a dropsied fish, have a look at this.....
http://puregold.aquaria.net/pg/disease/dropsy.html

This is not a one-fish success, JoAnn Burke has experience in goldfish diseases for over 20 years....