My google-fu has failed me and I know you guys are fabulous at this so I thought I'd come here
The designer is Adrianna Papell. I believe its technically out of her "Evening" line. I'm looking for a style name/number and possibly a season. I believe it also comes in a floor length design. My FSIL loves them but has only been able to find it in one location online where it was out of stock.
I've found one on tradesy and one one ebay in different colors but that's it.
Formerly known as flutterbride2b