Re: Augments
A list of all augments (in no particular order) and the effects they have:
Ghoul Augment: Drains enemy health.
NOTE: If you find yourself getting hit a lot, this can come in handy. Better on melee weapons than guns, since if you're ranging you might as well focus on not getting hit at all and increasing your damage.
Flame Augment: Does fire damage.
NOTE: At least, it says it does. I've done a lot of testing and I don't think it has that much of an impact. Even against Hollow men, which are supposedly weak to fire.
See also: Slash and Burn Augment, which does the same thing except it makes your character prone to scarring. You may as well use either augment, since dieing (and thus getting scarred) in this game is very very hard to do.
Killerwatt Augment: Does lightning damage.
NOTE: Again, I haven't ever seen anything indicating that this augment does any extra damage, or if it does anything at all. It certainly doesn't stun enemies the way the shock spell does.
See also: Storm Scar Augment. Same as Slash and Burn.
Fear Itself Augment: Causes NPC's to fear you more.
NOTE: You only get the effect if you unsheathe the weapon and "show" it to people. Since you get fear and hate from unsheathing your weapon ANYWAY, this is kind of a pointless augment.
Bewitching Augment: Causes NPC's to find you more attractive.
NOTE: Once again, the effect only happens if you unsheathe the weapon. This a weird augment, since some people will still hate you for brandishing a weapon, and others will be magically compelled to love you. Really, expressions are a far better way to manipulate NPC reactions then waving a magic weapon around.
Gnarly Augment: Makes you more resistant to damage, but more prone to scarring upon "death."
See also: Barkskin Augment, which does the exact same thing as the Gnarly Augment. One might be better than the other-- but how in the world could you possibly tell?
Stoneskin Augment: Makes you (extremely?) resistant to scarring. Whoop-dee-doo.
Golden Touch Augment: You receive gold for every kill you make. Not bad I suppose, if you're just starting out in the game when money is scarce. I wouldn't put it on your final weapons though.
Gold Burden Augment: Allows you to receive gold for every kill you make, but you will also deal less damage and have reduced defense.
NOTE: Crappiest. Augment. Ever.
[Rare] Discipline Augment: Gives you more experience for killing enemies.
NOTE: There is only one of these in the game, and it's located inside a silver key chest in the area behind Brightwood Tower.
See also: Cursed Warrior Augment. It gives you more experience, just like the Discipline Augment-- but it also slowly drains your health away. Making it a lame-sauce augment that no one would ever use.
Lucky Charm Augment: You deal more damage and take less as well.
NOTE: A very plentiful (you can buy and find them everywhere) and extremely useful augment.
[Rare] Devastation Augment: Increases your damage significantly.
NOTE: The most valuable augment in the game, hands down-- because it can be combined with the Lucky Charm augment for a serious boost in offense. There is only one of them, and it is located in Wraithmarsh. When leaving Bloodstone, take the left gate. It's in a silver key chest along the path to the Shadow Court.
Augments that can NEVER be found (At least to my knowledge):
Righteous Violence: Deals more damage to purely evil creatures, such as Banshees and Hollow Men.
Scourge: Deals more damage to lawful creatures, namely town guards.
These two augments are found only on two legendary weapons, and although I would be tempted to try them out in conjunction with other damage modifying augments-- I have never been able to find them.
With the exception of Slash and Burn, Storm Scar, Discipline, and Devastation. All augments can be bought.