I'm good at programming. What i lack is "designing".

I can write interactive code in PHP, but i can't bring up the look and feel of the webpage. I tried from various sources but could not reach to a point of satisfaction in this field.

Currently, I write HTML/CSS in any simple text editors like Notepad++, etc. but that does not bring up a professional, modern feel in the webpage.

On the whole, I want to begin web designing (only designing), already having a basic knowledge of CSS/HTML, but at a level far away from what I'm doind right now. I want to improvise my current skills so that I could design good User Interface for the users.

Kindly suggest me where should i start from, like whether i should start with Photoshop (but, I'm a total noob in Photoshop), or Dreamweaver, or....