For the OP: There are a few areas you will want to think about.
For general design, I like the book from this site:
http://gdbasics.com/
You also need to study type. There are lots of good options. A couple I know are : Stop stealing sheep (yes, that is a design book), Designing with type.
I also recommend a sketchbook(s) and develop all your ideas there first and don't go to the computer until you have a firm idea of execution. The computer is a device for execution - it cannot replace mental creativity. So, yes I am saying that photoshop filters DO NOT equal creative problem solving.
I would also look at the work of others but, not for the purpose of copying a style or look. You want to pull the design a part and figure out why they are successful and appealing to you. Just like Michelangelo did with cadavers. Looks at the type, the relationships. Look for the use of design principles. Once you learn to recognize them easily you will be on your way to being a good designer.
To those who claim software is half as important as design principles you are wrong - flat wrong. The creative process informs the execution, not the not the reverse. I see a lot of "graphic designers" who know photoshop but, can't successfully solve a design problem. The reason is they go to photoshop and expect to SOLVE the problem there and they usually just copy something they have seen. It's a false procedure. You have to come to PS with a solution that PS can help you execute.
-mx