It would also be helpful if you could post some samples of the kind of thing you would like to achieve. I get the sense that you're looking for help with style (how things look) rather than topography (where things go). There are lots of good Photoshop tutorials, guides, and case studies available, and we can certainly help guide you to them once we have a better idea of what you want to achieve.

Off the top of my head, you might find good information by searching the tutorials forum for threads started by Ascension and Jezelf. Also, a search for the phrase "[Award Winner]" will get you a list of the tutorials generally considered most useful.