A Primer on Death

In a world with resurrection spells, it's pretty easy to chronicle exactly what happens when you die.
First, the worst-case scenario. There are several things that kill you, but prevent your soul from travelling on. There is a long list of these, and the Valley boasts an impressive collection of them. Devourers are sentient undead who have soul-traps welded into their body. They steal the souls of those they kill, and use them to give themselves a boost in combat. A whole host of cursed soul-stealing objects are littered about the place, and there are certain spots in the world that are so distant from the other planes, the soul doesn't have the strength to pass on, and will often form into a malevolent undead.
Speaking of them, sometimes the soul chooses not to travel on. Ghosts and Wights are two creatures that form when a soul has some reason to stick around, usually born out of cruelty or malice. Revenants are what happen to holy warriors who are so dedicated to their cause they don't accept death, and continue to carry out their duties. Nearly always creatures formed in this way are mean and vicious, as they fail to move beyond denial at their own passing which slowly solidifies into a loathing of the living.
But, good news (relatively), you died under normal circumstances. What next? Well, your soul travels to the astral plane. It's a boring place of infinite undulating grey ground and a starless sky. You join the Great Line, and wait your turn to see Pharasma, true neutral goddess and judge of the dead. The line isn't boring however, you've got a lot of people about, who probably have an interesting story to tell. Some times the line moves slowly, and people organize games, classes or even impromptu theater to pass the time. 
Moving along the line are patrols from every alignment. The Astral Plane is a neutral zone, and everyone is watching everyone else closely. Sometimes devils or demons will try to seduce souls into signing some deal or making a bargain, and Good aligned outsides may offer a form of last rights or repentance for the newly dead. There are some native denizens of the Astral Plane, horrific things of rags and shadows that will attack and consume souls if not quickly driven off by the planar patrols.
Time flows oddly here, and how fast the line moves, and how far you are from the front is all a bit of a blur, even to the seasoned premium-resurrection-insurance-covered hero. The front of the line is The Spire, Pharasma's own castle that is so big it extends from her home plane (the true-neutral Boneyard) and into the astral. Once inside the spire, you meet with Pharasma herself. There, she will direct you to the appropriate afterlife.
Exactly what transpires next differs from person to person. Some know exactly where they want to go, and Pharasma is often happy to oblige. Sometimes she will offer to read your mind or chat with you, to try and find the best place. Sometimes she will send you in a certain direction, regardless of your wishes or protests.
So where do you go?
If you're such a staunch, unmoving atheist that no god wants you, your soul is turned into bricks and hammered into the boneyard itself, growing The Spire ever larger. Some souls actually desire this outcome, the welcoming embrace of a functional oblivion. 
If you're so plain or balanced that no afterlife really appeals to you, you become a citizen of the Boneyard. This is basically a massive city (with The Spire at the center), and is kind of a diet-soda version of life. There is no hunger, no aging, no disease, and no suffering. It still hurts if you stub your toe, but the pain is slight and fades quickly. You're basically left to do whatever you like, be it socializing, art, or just exploring. The Boneyard is so large as to be functionally infinite, and few souls ever get truly bored.
If you're none of the above, you're often herded to one of the aligned outer planes. They are all functionally heavens, but for a specific kind of person. The Chaotic-Good plane of Elysium is a wild place, ever in flux. Souls sent there live an afterlife of excitement and beauty in the ever-changing land. Abaddon is the Neutral-Evil plane, lovely and mostly populated by insects and rodents. There, souls tower over everything and forge themselves an eternal life of self-centered debauchery.
Even the most evil planes are heaven to a certain type of person. Each part of a plane is watched over by a god, and it's extremely likely that someone who faithfully followed a god will be invited to live in their land upon their death. Thyr has a massive castle in the Seven Heavens, where Lawful-Good souls debate laws and philosophy, and live a quiet, ordered life. Telephos has beautiful fields on the outskirts of the Lawful-Neutral Axis. There, souls that have spent their life sweating and toiling in his name are rewarded with a life befitting the mad stoics who follow him.
Some argue that life is more a sort of introduction or tutorial, and that the afterlife on the outer planes is where life truly begins. Whether you agree with that or not, it does mean that most people on the material plane are at least a little bit more calm and relaxed, knowing that death isn't always the end.