Reason's Jesse Walker has posted an RIP, which also discusses the interactions between Bookchin and libertarianism. Like many individuals on the left and right (Ronald Radosh comes to mind), Bookchin was willing for a period to ally with libertarians, which he later downplayed when he became more dismissive of libertarianism. To illustrate this, Walker has an amusing side-by-side analysis of Bookchin with libertarianism's Murray Rothbard, with whom he at one point collaborated on something called the Left-Right Anarchist Supper Club, but he later dismissed him as an advocate of "naked greed" with "repulsive" ideas.
I wasn't particularly familiar with Bookchin's stuff or his "social ecology" philosophy of eco-anarchism, but I've read a few bits. His famous New Left rant "Listen, Marxist!" was a critique of the influence of old-school Marxist factions like the PLP (Progressive Labor Party) in SDS, and the waning of the Old Left in general ("Marxists lean on the fact that the system provides a brilliant interpretation of the past while willfully ignoring its utterly misleading features in dealing with the present and future."). The famous "Marx, Engels, Lenin, Mao — and Bugs Bunny" cover on the original pamphlet doesn't seem to be posted online anywhere. He also contributed an introduction to Sam Dolgoff's anthology The Anarchist Collectives about worker self-managment by anarchists in the Spanish Civil War. This contains a delightful passage where he boldly sets forth Hegel's distinction between faith and freethought:
Hegel brilliantly draws the distinction between Socrates and Jesus: the former a teacher who sought to arouse a quest for knowledge in anyone who was prepared to discuss; the latter, an oracle who pronounced "truth" for adoring disciples to interpret exegetically. The difference, as Hegel points out, lay not only in the character of the two men but in that of their "followers." Socrates' friends had been reared in a social tradition that "developed their powers in many directions. They had absorbed that democratic spirit which gives an individual a greater measure of independence and makes it impossible for any tolerably good head to depend wholly and absolutely on one person.... They loved Socrates because of his virtue and his philosophy, not virtue and his philosophy because of him." The followers of Jesus, on the other hand, were submissive acolytes. "Lacking any great store of spiritual energy of their own, they had found the basis of their conviction about the teaching of Jesus principally in their friendship with him and dependence on him. They had not attained truth and freedom by their own exertions; only by laborious learning had they acquired a dim sense of them and certain formulas about them. Their ambition was to grasp and keep this doctrine faithfully and to transmit it equally faithfully to others without any addition, without letting it acquire any variations in detail by working on it themselves."Less worthwhile is Bookchin's grumpy tirade Social Anarchism or Lifestyle Anarchism: An Unbridgeable Chasm against bohemianism and individualism, especially its hatchet job on individualist anarchism and ethical egoism. (Given his weary dismissal of a good chunk of anarchism, I wasn't too surprised to find out that he abandoned anarchism altogether in the last few years of his life in favor of "communalism".) Perhaps the most tantalizing item on his bibliography is two broadcasts on WBAI, "The Transformation of our Environment" (1962) and "Economics as a Form of Social Control" (1974). Also, Matt Hern's Field Day is an outstanding critique of the culture and politics of schooling, largely from a Bookchin-influenced social ecological perspective.