I found the contact form:
This is what I wrote (I am quite curious if I will ever get a reply)
I am truly disgusted with one of the products you sell on your website. There is a set of 'whimsical' cat pictures containing one photo of a morbidly obese cat. To allow a cat to get this fat is animal abuse, and to portray it as as 'art' is beyond bad taste.
In offering this picture for sale, you are condoning, even promoting, this serious form animal abuse, as well as justifying insults to obese people. Obesity is very unhealthy, and therefore NEVER funny, and presenting it as such, in humans or animals, is insulting and disgusting.
Please stop selling this item and remove it from your site straightaway.
I know I am not the first to complain, I was alerted to this item by several British cat lovers, who ALL have written negative reviews or mailed their complaints, but you are too chicken even to own up to your mistake by showing them.