http://pagetemplateplugin.com/ – How to add a sales page to WordPress that’s still part of the WordPress “loop”. This clever plugin allows you to write your sales copy in the TinyMCE editor and then choose a pre-made sales page template to display it. If you don’t like the look of the template, just choose another one.
You can easily move blocks around on the page (using short code tags) such as the testimonials, guarantee certificate and buy button.
The Unified Page Template Plugin greatly simplifies the entire process and even allows you to add squeeze pages to your WordPress blog too.
Using the plugin, all page template designs will work with any theme and also survive theme changes.