*blushes* Oh, I'm just so flattered by your comments. Actually, I don't really consider myself an artist, but the majority of the things I've done look exactly like this. Though I suppose most of what I do for fandom is the sketchier cartoon art. This is really just that art with more detail.
As for making posters, I honestly have no idea. I don't even own Photoshop. But I'm flattered you'd want anything of mine. You really made my day! *hugs*