cptnwinky has a lot of useful information in his post, but there's a few things I'd like to add.
First, I believe a more industry-wide standard for the top bar on a website is called a header.
The header can contain the title, a motto, graphics, all that kind of stuff you see on the top of websites. Also, it can contain the links, such as these forums do. Followed by the header, is the body, which is obviously where all the content goes. Of course, there can also be side bars in the body also containing links.
Bottom of page - footer. Copyright stuff, extra links which may not hold as critical information.
You may or may not know all this, but oh well, the basics are good to know

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I got into webdesign and everything by first reading various tutorials on HTML and CSS, learning the basis of everything. From there, I first tried formatting stuff with what I learned, and then I moved onto playing with templates themselves. IMHO, downloading free templates, reading through the source, editing them and figuring out how stuff is displayed is one of the best ways to learn. But once again, thats the way I did it, and may or may not apply to you, or others.
I have a lot more useful (I believe) information about starting off in webdesign, so if you'd like more assistance, please feel free to PM me!
Good luck