"Paths of Prestige" by various, published and distributed by Paizo Publishing.
This slim 64 page addition for the Pathfinder Campaign Setting adds 30 new prestige classes to your favorite Fantasy role-playing game.
Section One, "Arcana", has 8 new mage prestige classes, including the Arclord of Nex, the Blackfire Adept, the Magaambyan Arcanist, the Razmiran Priest, the Riftwarden, the Tattooed Mystic, the Veiled Illusionist, and the Winter Witch.
Section Two, "Brawn", has 9 new fighter prestige classes, including the Aldori Swordlord, the Brother of the Seal, the Golden Legionnaire, the Knight of Ozem, the Lantern Bearer, the Mammoth Rider, the Pit Fighter, the Shieldmarshal, and the Skyseeker.
Section Three, "Guile", has 6 new rogue prestige classes, including the Aspis Agent, the Bellflower Tiller, the Daggermark Poisoner, the Gray Gardener, the Noble Scion, and the Sleepless Detective.
Section Four, "Piety", has 7 new clerical prestige classes, including the Champion of Irori, the Dawnflower Dissident, the Green Faith Acolyte, the Hellknight Signifier, the Prophet of Kalistrade, the Storm Kindler, and the Umbral Court Agent.
There's also a chart showing where to find 36 other prestige classes. The classes in the book are presented in alphabetical order. A canny GM would look to see if any of these classes would be more appropriate for NPC's. There are two pages for each class, and the necessary chart, as well as a sample picture of what a generic member of that class would look like. All new prestige classes in this volume, and references to the prestige classes in other Pathfinder products, make this just about a must-have for GM's. Highly recommended.