Give yourself plenty to time to look. The perfect dress is out there waiting for you. We had a big bash for ours some 8 years ago now - oh God I feel old! - and I made it black tie so the girls could dress up! I found the perfect thing in silver with a small bolero. Took a bit of trawling round but it was worth it. It is the nearest time you get to being the centre of attaction again, since your wedding day, so make the most of it!! Enjoy!