It's actually pretty simple to do it yourself when you start thinking of how everything separates. When you write the HTML, think less about what it will look like, and more about what containers you'll need for what content. Write all of that first. Don't touch a bit of CSS until you at least have a skeleton down.
For example, let's say you want a header area with a logo and a nav. Below that, you'll have a content area and a sidebar. Below that, a footer.
Start by laying down the basics you must have. You could maybe keep a file that already has this, or perhaps if your editor has a snippet function, use that.
HTML:
<!DOCTYPE html>
<html><head>
<title><!--Whatever--></title>
<link rel="stylesheet" href="style.css" />
</head><body>
</body>
</html>
Then, just start blocking out what you know you'll need, not even worrying about what it'll look like.
HTML:
<!--DOCTYPE thru open <body> tag from above go here-->
<header>
<div class="logo">
<h1>Site Name</h1>
<h2>Tagline</h2>
</div>
<nav>
<ul>
<li><!--Menu Items--></li>
</ul>
</nav>
</header>
<div class="content">
<!--Main content stuff will go here-->
</div>
<div class="sidebar">
<!--Guess what goes here-->
</div>
<footer>
<!--FOOOOTTTTEEEEERRRRR!-->
</footer>
<!--</body> and </html> from above here-->
Took less than 5 minutes, and right now there would be literally nothing there. We've defined no visuals and frankly have no idea what we're going to make it look like. We don't even know which side the sidebar will be on. The important thing is, however that we have the structure of a basic page in place. From here, you can easily begin to think of how you want the various page elements to look and where they'd be. Using floats along with the box model and positioning, you can do quite a bit with just what we have here. My main point is that when you try to style elements as you go, you run into more problems because the structure isn't in place already. You can't see what you're going to be working with 20 minutes down the line, let alone several hours. But, when you get the structure down and in place, you can see what you'll have to work with ahead of time. You can begin to visualize how things will react to what you're doing. You may find, as well that your CSS comes out cleaner this way. I did.
You
could use a site builder for it, and there's no shortage of them out there, but why would you when it's this simple?