Display all products in columns, instead of 1 per line?

Currently as I add products, they display on product page 1 below another. So the image and description of 1 product takes up a whole "row" so to speak. But when I look at your demos, I see 3-4 products across. Is there a way to do this without having to use the framemarket theme or changing my theme? We've already put a lot of work into our current theme.

You can see my product list at:
http://lynettejoeldesigns.com/store/products/
Also, I can't get the description of the product to go anywhere (lower in respect to the image) or under it. It looks funky, probably due to my theme, but I couldn't figure out an mp_product attribute to change.

---I found the CSS for the marketpress plugin and the layout.css under COLOR PICKER folder. Is there somewhere in one of these css files that I can set up products to display 3-4 across instead of 1 per line? I don't mind if the description is suppressed until the customer is on that specific product page.

Thanks,
Susan