heh, not too bad :P
few things, defiantly use references! always! lots!
Try to avoid 'tris' (a face with 3 edges and 3 corners), use 'quads' (a face with 4 edges and 4 corners) wherever possible.
Try to get a pretty even spacing of the faces, some of your faces are long or wide, some parts have lots of faces other parts few. This will help you a lot later when you use sub-surface to make your models smooth and pretty.
Looks cool though, what method did you use? Start with a cube and extrude?
Here are some render settings I like to use just to make it a little prettier;
Here
I use 16 times over sampling, with a 1.5 radius to get rid of any dodgey looking edges, I also set it to PNG render format, and use RGBA so that the background colour is instead transparent (looking at your avy you know all about transparency :P), just makes it look better imo.
Oh, and if you want to subsurf it; F9 -> Add modifier (right most panel) -> Subsurf
and change the render setting to make it smoother.