how to add custom bar at top all pages?

We want to put a special bar across the top of every page. It's made from a complicate little bit of html, which i've made into a block, and it uses a special style sheet, which i've listed in the .info file for our theme. The theme is a hacked version of Acqua Marina with our own colors, decorative images etc. What is the best way to assign a block to the top of every page?

I already tried defining a new div class "header-top", modified the style.css, page.tpl.php and the .info files. The header-top region did show in the drop-list in the blocks admin page. It all sorta worked, but the bar displayed badly, and i wasn't able to figure which class or id or whatever from which file was confusing it... though i *did* discover the wonders of firebug 8D

The bar looks okay in a minimal hand-coded html page, using only the bar's css and a generic one, all from outside of drupal. I'd like to try defining a region above the header, but before i get back into performing code surgery i guess i should go against my nature and actually ASK!