I took a glance at my header a couple days ago, and I realized that it looked ridiculous because it did not go entirely across the top of the page. So set about trying to fix it.
I went through multiple suggestions on other blogs. None worked. And I messed up my blog for a few hours.
Then I stumbled across Yoboy's solution at Southern Speakers. His "Method 1," where you go in and edit the width in the dashboard, didn't work. "Method 2," where you go into to the template and add html to the CSS, did. I had to tweak alittle, but I really appreciate the solution.