I'd recommend Will Storr vs. The supernatural, which I recently re-read.
It's basically a personal investigation into the reality of ghosts in which the author interviews mediums, exorcists, investigators, philosophers and psychiatrists, Maurice Grosse - and even Janet herself (the Enfield poltergeist Janet, that is) - joins a few vigils, and even dabbles in quantum physics.
The book starts from a fairly sceptical perspective, but doesn't stay there for long - actually, a large part of what's so entertaining, and what makes the book so humane, is watching Storr wobble from scepticism to belief and back again as the evidence piles up on either side of the argument, and depending on how shit-scared he has been by his latest experience. Storr makes a great Everyman: a mix of open-mindedness, scepticism, belief and inquisitiveness, all shifting around in response to new experiences, opinions and information - and how dark it is outside
On the sceptical side - I'm no lover of Most Haunted, but, even if I was, there is in the book one simple piece of evidence which Storr stumbles on while at a recording of the programme which puts the final nail in the coffin of it's credibility (at least as far as I'm concerned). And Storr meets his fair share of charlatans, the misguided, and the oh so utterly desperate to be special - although, to his credit, he's pretty gentle in his treatment of them and tends to leave the obvious conclusions to the reader rather than make their mind up for them.
I've seen the book described as 'lightweight', which I think is a little unfair - or, at least, gives the wrong impression. Okay, it's not an in-depth work of scientific research - Storr is a journalist, and the writing has a light and easy to read touch but, at the same time, it manages to cover some pretty complex ideas.
Possibly the most disturbing point in the whole book is towards the very end when an obviously disturbed, but hardly 'possessed', child is 'exorcised' by those who appear to be desperate to believe that his problems are due to satanic intervention. Storr, to his credit, tells those concerned that what he has witnessed is child abuse. However, there's a bit of a twist - one which would sit well in the best of movies.
I'm not going to spoil it.