What I always love to do with these type of catalog sites... Is create one "big idea" for it and then open with a personal message from the "President" of the company that invites them to start shopping.
Basically, this means intense target audience research. What do they want? Why do people buy dog clothes (honestly, I wouldn't know if you had a gun to my head... I suppose vanity and social status has to do with it, but I suspect there's more to this)
And then build a "great idea" around it, and write up a headline that stops the reader dead in their tracks... Then follow up with the personal message from the President of the company that gives them a compelling Reason Why this is the best way to shop for dog clothes.
Then start off with 3 best deals for instance, and smaller text links to different categories. Make it easy to delve into what they need after you've established a "Reason Why"
I wouldn't push this with seperate direct mail letters as some suggest for catalog sites... but then again, I'm not expert at this, I've only done 2 sites like this so far and am working on my third.
Owner's ecstatic but no results yet... Maybe others have more experience with this
In any case.. Good luck!