I stumbled across Charles' (Kod) Art Blog. There is some older concept art I had never seen that I wanted to share. There is also concept art for The Secret Of Space Octopuses as well as what looks to be a futuristic racing game (my favorite kind) called Ring Race. The concept art of the Ring Race vehicles look strikingly similar to the vehicles in Hover. I'm only going to share the Hover art here. But I will provide links to the other stuff mentioned below.
Charles Vesic Art Blog Home Page
2D Concept Art Blog (Environments)