There is a tutorial at Hybrid-Genesis that is pretty good. It's more artistic than most of the headers and banners that I make. Almost every tool used is a PS default and she is really good at writing tutorials so it should be easy to follow.

http://de-hybridstyle.com/insomniac_free/header_tut/header_tut_p1.html

If you want a header or layout right now I could probably have something made by tomorrow, for you to use until you make something you like.