From png to code

I'm not new to CSS as much as I am to slicing up images and making them become designs..

I made a mock up header in a png file (http://www.leerecs.com/lookin_downers) that I actually want to be html and css.

So far I've gotten to the menu, http://leerecs.com/headermake.html
But even then, I can't get the text box (for searching) and the search button to align side by side as they do in the image.

Any help regarding tricks, advice or articles that I could read on making these designs reality would be nice. I'm having a lot of trouble with this basic header and I'm sure it's because I've no real background in this...

Thanks (gracias
Mark