PR is a product of links... so you need links.
A drop-ship-site-in-a-box website, for example, will have trouble ever ranking for anything since it's just like a bunch of others already out there.
But if you take your prepackaged website and add great content like better descriptions, customer reviews, suggestions on how to use the product and detailed support information.... it's suddenly worth more than the other site-in-a-boxes.
Do some research, think about what makes your site incredible, then use that to market/promote your site.