I just had a look at your site. You do really nice work!
Hi, I am new to css too. I used to build websites but took time off to start a family and wow, things are really different now!
I started using http://jigsaw.w3.org/css-validator/ and http://validator.w3.org/ to work on fixing markup and css issues. If you try this it may help you understand more of what you are doing. It is helping me.
I had the opposite problem than what you have. The site I am working on looked fine in IE but looked crazy in Firefox. I was able to play around with the css and make some adjustments so it looked right in both. For me it was trial and error (mostly error =)).
Here’s another url to help understand the difference in Firefox and IE: http://www.search-this.com/2007/03/12/no-margin-for-error/ It seems as though margins are quite different in the two browsers.
