In fairly exhaustive detail (and helpful outline form), this Stanford Encyclopedia of Philosophy article covers neoliberalism, its history and development and its current state of art.
Neoliberalism is the still the default political philosophy of the western industrial democracies, and needs to be comprehensively understood by everyone.
At its most basic, neoliberalism is simply the intersection of capitalism and representative republicanism.
A critical conclusion is that
neoliberalism no longer faces greater analytic hurdles than other political positions like conservatism or socialism.
Or to put it in other terms, neoliberalism does exist and scholarship is gradually coalescing around a coherent view.