There is a really good book out there on one person startups called the $100 startup by Chris Guillebeau - it gives loads of examples of startups around the world, which were started by one person (http://amzn.to/1Kb63VH)
I have read that book; Its definition of a startup was affiliate marketing or selling courses on selling. There was few examples of real businesses like Coffeeshops or a Photographer but I don't think we consider those startups.