StudioPress itself is somewhat of a niche product as it is targeted to existing WordPress users who found setting up and managing a WordPress site too difficult or time-consuming. StudioPress prides itself on being easy to use, but their main claim to fame is that their hosted websites are “faster and more secure” than other WordPress hosting companies as well as using the “Genesis framework” which is supposedly more SEO friendly than other WordPress builds.
If the above locations do not yield information pertaining to affiliates, it may be the case that there exists a non-public affiliate program. Utilizing one of the common website correlation methods may provide clues about the affiliate network. The most definitive method for finding this information is to contact the website owner directly if a contact method can be located.