Even though i just help moderate the forum (though honestly, nothing ever happens here), i'll try to answer this. I'm probally wrong, so don't take this as the final say by any means.
If Kazu likes what he sees in your work, he'll probally ask you to be a contributor to a future volume. So the best way to demonstrate that is by posting on the forums and show everyone here how talented you are. If you have what he's looking for, i'm sure you'll get a message from him.
Kick ass pic of Astroboy by the way! By all means, show us more!