Visions of Purgatory: A Private Revelation, I am making an exception.
Why? First, the book has a preface by Bishop Henri Brincard, Bishop of Puy in Velay, France, who states, "I would like this account, beyond its particular form, to revive devotion to the souls in purgatory and promote beneficial reflections." Second, the book is published anonymously. No one is seeking to get famous off of these revelations. Third, there is nothing in this book that contradicts anything that saints have told us about their own visions of purgatory. The book is extremely well annotated to emphasize that fact. Four, like Bishop Brincard, I want to help people understand how important it is to pray for souls who have died.
So many times, at a funeral, people will talk about how someone is in heaven. I know it is comforting to think that, but the simple truth is that we don't know. That person may be in desperate need of our prayers. When I die, I want people to pray for my soul! It is an act of love to pray for our family members and friends who have passed on before us and to have Masses offered for them. We can have Masses offered even for those who were not Catholic. We also should pray for the souls in purgatory who have no one to pray for them. This is part of our responsibility as a member of the communion of saints.
Almost everyone who is ultimately destined for heaven (that's the good news) spends some time in purgatory. This includes children who have reached the age of reason, members of every faith, priests, and religious. Even many canonized saints have spent some time in purgatory. While we should do all we can to avoid sin and do penance here on earth, we have to be made perfect before we can enter heaven. All the vestiges of sin need to be purged. "Purgatory was created by mercy - the souls are in purgatory by a decree of mercy and the pure gratuity of divine love. For these pains, no matter how terrible they are, are very slight in relation to the offense that sin constitutes."
I encourage you to read this book. It offers a real glimpse of what purgatory is like. Even if you don't read it, however, please remember to pray for those who have died every day. That is the most important take-away from this book.