So I'm working on making a web site as standards compliant as possible and have made use of the border-spacing property in my tables (of data) extensively. Of course, now I find out that IE doesn ...

Open your CSS file in a text editor, such as Notepad. Click your cursor at the bottom of the file and insert the following code:table.nospacing { border-spacing: 0; }table.nospacing th, td ...

It ought to. You might need to fool with the table's properties (in HTML, the cellspacing and cellpadding attributes, or in CSS, the table's padding and border-collapse properties).