Gave it a go, since it was a reasonably simple shape. You're on your own for gibs, I'm afraid, but carving the ship up should be the easy part (and kitbashing some stock debris in).
5jFC482_steel.png
Regarding sketchup, it's not a bad tool to learn I suppose, but I'll be honest (and speedoflight, no offense intended), I don't care much at all for the appearance. The Omicron ships have a very unique look, but feel very out of place in FTL, at least to me.
As far as Photoshop goes (or GIMP), all that's really required is to import your sketch, make a new layer, then trace over it with a 1px brush to get the outline. Can be a little time-consuming, I suppose, but it's not a terribly difficult process. After that, it's just a matter of playing around with the right gradients (and I grant you, I didn't spend a great deal of time with the above concept, could probably smooth it out a lot more if I were more careful).