@EDM Assassin - StudioPress has a showcase of websites that were built with their child themes and with 3rd party child themes they sell in what used to be their marketplace. I'm not even sure how you get sites listed in that showcase anymore... I've submitted 3-4 sites to it over the past 2-3 years, and have never had a site get listed.

They don't have a comprehensive listing or catalog of Genesis child themes by other developers or good ones that are on other marketplaces like Theme Forest or Mojo Themes.

One site I've seen with something similar is the Themes Directory at wplift.com, but they list all sorts of themes from other frameworks and standalones, too.

I wanted to build something that was only Genesis focused, and it was a discussion in the StudioPress forums that led me to start putting together genesisthemesguide.com. Now I just have to keep adding more Genesis child themes other that SP options, and work on gathering or writing documentation for some of them.