For the AC/DC trophy, you can continuously suck energy out of the transformer you must reconnect in substations.
An easy way to get the AC/DC trophy, is to go into a substation (underground) and while you're draining energy press the PlayStation button. Make sure to not let go of the drain button until you are on your home XMB. Wait for a few minutes, walk away do, whatever you fancy. In order for the trophy to pop, you have to stop draining energy.
For the good/evil trophies, you can save before a mission. Beat a level being one Karma, then reload and do it as the opposite Karma.
For the Truly Infamous trophy, you can activate the Ray Sphere, which will instantly (and permanently) set you to Infamous rank.
For the Doctor Cole trophy, you can knock someone down with a punch, then heal them. Repeat this over again until unlocked.
For the True Potential trophy, purchase all of the upgrades for Melee, as they are the lowest in cost and all of them are available from the beginning. They are also not specific to your Karma (unlike certain powers, such as Arc Lightning or Overload Burst).
For the Drop Everything trophy, you can thunderdrop from the top of Alden's tower in the Warren district, once you have unlocked it.
For the Frequent Flyer trophy, you can also use your Static Thrusters after hopping off the top of Alden's tower as mentioned above, if you don't get the trophy the first time, you can repeat the process as many times as you need until you gain it.