Need non-urgent help with positioning



So, some years back, I joined a group that had some projects available to help keep people coding. I joined one that had to do with making a website design for a pet shop. Looking at it again with fresh eyes, I realize how much I didn't know, and how ugly my first attempt was. So now I'm making a second attempt at making a much nicer version, but as usual, positioning is determined to stand in my way.

As it stands, I'm not really worried about the margins, I'm still deciding what I feel looks best based on what it's supposed to look like when it's finished. But I don't want to add any more images until I get it positioned how I want. The problem is with my second set of divs, which is the "Pet of the Week" and "Recently Found a Home". They have an enormous amount of space between them, and I'm not sure if how I have them is the right way to go about it. Not to mention, their layout seems to change depending on the margin. I also did a bit of googling to figure out how to get the image and text on the same line.

Here is my codebit.

If you have suggestions on other things to add to the page, don't hesitate to toss them in. Also, yes, I intentionally left the shadow off the header. And I haven't gotten around to making a footer, even a minor one. I'm also thinking about making most of the divs bigger, not sure if I'll do it.