hey tamlin that's a great start!
i think you can really add to what tamlin's done by adding a 'reflection' layer and then distort it so it looks like the metal is bending around the body...you can find a lot of HDR images out there...and then add some scratches, and adjust the lighting on it so it matches your photo's lighting better and all that jazz...
also if you find some good references onto how it looks... you could even go so far as grabbing a hi-rez image and just doing some clone stamping on it.
here's somethings that came up when i did a google search...
http://sussen.com/photos/vH033c.jpg
Suit of Armor hand made by sculptor and artist Bruce Gray
http://www.swordandstone.com/armour/...mei_armour.jpg
Google = searchy goodness