Best way is to always check the source of pages that you like so you can have a clue of what tecniques they use.
Even i'm not creative at all but, i can create very attractive designs. Thanks to this book called http://www.sitepoint.com/books/design1/. I recommend you to read it.
start out with little banner designs... a few colors, pictures and text would be fine... and don't forget to learn the power of pen tool... it is really helpful...
Learn the photoshop basics to get more familiar with the program, the start trying advance tutorials (www.good-tutorials.com) it takes time.. and a lot of practice.
A lot of the art of designing is trial and error. You learn what works and what doesn't. You may want to get your hands on some free templates and dissect them to see how they work. Once you have the feel for how the CSS works for those deisgns, you can use them as a basis for your designs and then elaborate on them. Nobody is going to be a great designer right out of the box.
Start with photoshop then go with tutorials. It takes a lot of practice though. When you keep on designing, i believe you get better after each design.
Yes, I agree photoshop is the way to go but you may also want to experiment on some new softwares out there.
I Have the problem like U But not too much. So when I want to be a designer, I Write the idea on paper and forget all coding.Just Imagine.
as if no one has suggested this yet, but learn valuable lessons on design here: http://webdesignfromscratch.com/
webmonkey.com but also, everything that i look at, i ask myself why i like that, why i don't/what i would change. it helps me to formulate ideas a lot faster when working on a project.
You know what might help you... go to a graphics generator on the web and experiment (i.e. cooltext) and learn some of the techniques in graphics on other sites and just start copying with your own style that will build into your own unique artistic style.