Seems like you understand some basic blending techniques, as well as an understanding of the program you're using. I'd just reccommend reading lots of tutorials (available in the resources thread on this forum), and incorporating different styles and tuts into your work. But your work is fairly solid for a beginner. Don't mistake it for magnificent talent, but it's a much better base than a lot of us start from on this site.
Browse other threads, read tuts, experiment with PS (or whatever program you're using), etc.