Here's his UK cover for Worldshaker:
And here's a sneak preview of his UK cover for Liberator:
That's the great battle from the end of the story - recognise the Russian juggernaut, the Romanov? Further in the background, you can see the Grosse Wien and the Marseillaise too.
There are hundreds of Ian's amazing illustrations on the web. Check out
I'll just paste in a couple - an image for the Difference Engine, which goes with Gibson and Sterling's famous steampunk novel of the same name:
And a couple of his fabulous, gnarly, almost mechanical, insect cum bird creations: