tutorials for doing web page layout?

so i just learned html and css and studied one of the web sites i found(a simple one with white background) but now i'm seeing a lot of web pages with special background images and images for menu bars, and etc.

Now i realized that a lot of the times people would use a small image and repeat it so they could have a more fluid background that could be easily adjusted, instead of a fix background image.

So basically they would create a visual layout of the web page using photoshop (creating what the page will look like (one big image)) and then just chop up the image into different parts... .some for menu, some for background...and use them accordingly right?

Does anyone know a good place to learn about doing web page layouts with photoshop?

i know for html and css there's htmldog and w3schools, but what about for photoshop web page layout type stuff?