Sitepoint's website marketplace can be used for conceptualization of the business model - determining what kind of website to create, what niche to target, where the revenues come, etc. Analyze auction bid and study the value of niche sites.  Get info from site sellers such as details of how they built them, web traffic, revenue source, etc. It is a info gold mine!  Learn what business models and niches are working for other people, and adapting them with your own ideas.