@livejamie and @dynamicduo give the best advice here. It really is your portfolio above all. Degrees and certificates are near meaningless in most cases. A degree is usually only required for a job at a large company that has college requirements for all their jobs (Google, etc.).
Photoshop, HTML and CSS. That’s all you need. Photoshop is used to create graphics for the web and to create “mockups” of websites—that is, preliminary versions of websites before they see production.
JavaScript is nice but its a distant fourth and you don’t need it for a few years into your career, generally. It depends on what you’d rather do. The title of “web designer” refers to a varied collection of jobs. Doing all of them early in your career lets you figure out which one you’d actually like to do. Of course, it could be that you want to do them all, as I generally do. The various occupations include:
* Visual Designer
* User Experience Designer
* User Interface Designer
* Web Developer
* Graphic Designer
* Web Producer
* Information Architect
* Usability Expert
* Webmaster
You could also work in the medium of Flash which is used for complex applications or sites that require dense multimedia like animation or video.
And lastly, I can’t disagree more with @jw. Dreamweaver is not a language, it’s an application. You use it when you don’t know HTML and CSS, it automates the languages for you. I would recommend skipping Dreamweaver and applications like it (called WYSIWYG editors) completely. They produce terrible code, among other problems.
I’m not sure what is meant by the point about keywords. Considerations like writing for the web, usability and search engine optimization (which all have to do with word choice) are all more complex than has been touched on here.
How much you should charge is a another completely new topic altogether and essentially comes down to how much you’d like to make vs. how much others are making for what you do. This requires research and reflection and has very little to do with the content of the website.