As far as the light goes, I highly recommend a light that uses an LED, as opposed to other types of lamps. My experience in Iraq was when the battery was starting to get a little low, other lamps would turn yellowish, sometimes making it hard to distinguish things. The LED lights that I have however, just get dimmer, but stay white. Plus with LED, you wont burn out a lamp and have to replace it.
As far as lasers, I don't personally use one, but I've heard good things about the Crimson Trace lasergrips. You could also look into those laser spring guide rod's. No experience with them, and haven't heard much about them.