Hi ben, Your general theme's CSS sheet can control it. --- For the product page and the image being to small I believe you can change that in here: http://www.yoursite.com/admin/settings/imagecache

Click on the product tab, it should say 100px x 100px You can change that to the size you desire, then hit update preset. You might have to re upload some of the photos to get them to cache again.

I hope this helps, - Justin