i dont think this is just an outlook problem. i seem to always have a problem with removing the white space around headings (and before paragraph text begins). my css has a lot of display:inline and margin:0;, and they look fine in web versions. then in email it goes kaput.
the other alternative is to put my headings in table rows, but this is a pain in the butt for each story.
Would you post your code here? Someone can take a look and see if we can spot why the spacing is off in Outlook. Also, which version of Outlook are you testing in?