It's difficult to say. While I don't personally subscribe to the thoughts or rituals of any one major religious organization, I find myself drawn to the idea of an afterlife. Not because of any subconscious longing for something to fill some sort of metaphysical void, mind you, but from my studies in Physics, Biology, and Chemistry. There is no difference, atomically or chemically, between a living entity and a dead one of similar species, therefore I must conclude that there is something intangible, beyond our understanding that propels these organic shells.
However, if this driving, motivating force (we'll call it a soul for simplicity's sake) cannot be detected by our own senses or the machinery cultivated by our society, then it is clear that any form of communication between our earth-bound selves and their ephemeral essence is impossible. So, do I believe that when we die, something that is "us" leaves our body behind to go do...whatever it is that shapeless masses of undetectable energy do? Yes (My current imagining likens it to a sort of cosmic amalgam, wherein all such energies coalesce when they leave their physical form behind). Do I believe these wingnuts like John Edward and his ilk can actually communicate with those energies? No, not in the slightest.
TL;DR: There are probably entities that exist that could be construed as "ghosts", but the idea that anyone could actually commune with something we can't readily detect via man or machine is laughable at best
