There are a couple of misconceptions occurring here.

First, congrats on the fine work to date

I too have parts of my body that aren't "filled up" any longer, and appears to be loose skin. Time will tell if it shrinks over a long period.

On the bodybuilding ailment you describe, I'm sure you don't have gyno, which are hard deposits under the skin behind the nipple that have to be removed by surgery, and caused solely by aromitizing steroid use. Most likely, you just have soft tissue thats caused by too much Estrogen in your body. I have this as well.

When you are done dieting, there are 3 options for removal:
1. Liposuction
2. A topical product using Yohimbe (a couple of popular ones are Yohimburn and Lipoderm). These are available at most on-line nutrition stores.
3. An oral product called Nolvadex (originally a cancer drug for women). This is what bodybuilders use after a steroid cycle to prevent Estogen rebound. The guys with gyno would have forgotten to use a product like this. Its available as a "research compound" on a few nutrition sites, or from an offshore pharmacy, because you are supposed to have a prescription. A Doctor knowledgable in sports medicine can get you a script.

I would try the topical first (it is the least potent), and then go for Nolva.