I recently found this definition of Neoconservative. This strikes me as being a pretty good definition and I think it would be hard to dispute this article/definition as it comes from something called Conservapedia.
Here are a couple of statements from this article:
Neoconservatives are often preferred by liberals to portray the conservative voice in the media, as in television talk shows, newspaper columnists, magazines, think tanks, and advisory positions in Republican Administrations.
This is not a new concept to me, although I don't think I have seen it stated this forcefully.
Wilson, FDR, Harry Truman, JFK, LBJ, Carter, Clinton, Obama, it is hard to look at this list and not see the architects and engineers of empire.
Glenn Greenwald is this era's chronicler of the process, see here,
Paleoconservatives, who dislike Neoconservatism intensely, have argued that it emerged from Trotskyite theories, especially the notion of permanent revolution. There are four fundamental flaws in the paleoconservatives' attack...
Paleoconservatives are basically what used to be called the Goldwater wing of the Republican Party, and before that, the Taft Wing. Their opinions are currently being "aggregated" here.
I think Gore Vidal summed up the process, found here:
There is only one party in the United States, the Property Party...and it has two right wings: Republican and Democrat. Republicans are a bit stupider, more rigid, more doctrinaire in their laissez-faire capitalism than the Democrats, who are cuter, prettier, a bit more corrupt—until recently... and more willing than the Republicans to make small adjustments when the poor, the black, the anti-imperialists get out of hand. But, essentially, there is no difference between the two parties.
UPDATE: See here