Wizards of the Coast has put out another book in the Complete Series: Complete Scoundrel (http://www.wizards.com/default.asp?x=products/dndacc/957277200).
This adds onto Complete Adventurer, Complete Arcane, Complete Divine, Complete Psionics, and Complete Warrior. Boy, as a previous DM I have to say that even just allowing the Complete series now makes for a *lot* of material to have to learn...