2x2 Sidebar Grid CSS Issues

I am trying to get my sidebar grid to do a simple 2x2 block in my sidebar. I spent about 9 hours yesterday digging around in CSSEdit and came away with virtually no more than I started. I think I may have pulled out my last strand of hair sometime around midnight.

At one point, I managed to get the layout just perfect, but then it threw the icons for the links way off to the right. Also, when it looked perfect in Safari and Firefox, it was completely wrong in IE7. So I finally got pissed and undid everything I had been doing and started back from the beginning.

Can someone take a look at my site, extract the styles.css and wpg2.css, and maybe tell me where I'm going wrong. I've tried virtually every variation between my styles.css and my wpg2.css and I can't for the life of me figure out what's causing the layout issues.

Here's the link:

http://www.quovadam.com

Thanks to anyone who can and will help.