Hi cyb3rpunk, welcome to the forums.
As people have already said, the best way to learn is to practice. A lot.
As for getting some tips and pointers, the workshop tab at the top of the page has some good tutorials and tips (although it is a bit of a nightmare to navigate) http://www.imaginefx.com/-2287754330326480692/Workshops.html If you feel confident enough, the challenges on these boards are a good way to learn too.
Above all, don't be afraid to ask questions. These are some of the friendliest forums I've ever encountered and most of the very talented artists here are more than happy to answer questions or offer advice.
http://infinatepixel.deviantart.com/