tim.....looks like brom signed off. On the page you're wanting to change, I assume you're wanting to get rid of the white there as well, right?
In the stylesheet that brom lead you to, find these:
.zmpi01 (image background)
.zmpi03 (Add to Cart box background)
.zmpi05 (Description box background)
These, you won't even have to change the colors.......just remove the:
background-color: #fff
and you'll be all set.
Also, I noticed that you haven't closed a lot of your code, like the one above, and a few more I saw in your stylesheet.
your should ALWAYS close each one with a semicolon. Like the one above should be:
background-color: #fff;
Hope this helps.
Oh.......and your breadcrumb background color doesn't have the pound sign before it:
background-color: d9d4b0;
Should be:
background-color: #d9d4b0;
Thought you might want to know that.