I have been picking up TONS of mana potions, but I cannot find them in my inventory to take at a later time. ( I am a wizard ) Do I automatically consume them when I pick them up? Or are they located somewhere else (such as a passive ability) ?
There are only healing potions in Diablo 3. The other items on the ground (they look like orbs to me) are absorbed immediately but I believe they are health related as well until you have skills that make them a bit more effective. The effects of these skills are tied to the class like Pound of Flesh for a Barbarian and Power Hungry for the Wizard that you are.
Here is a list of the potions that are in the game.