I do a fair amount of riding at night. The advice on rear lights is spot on - they are there to make sure you are seen.
Front lights serve two purposes - to be seen and to see. I've had really good luck with 3 brands - Niterider, Stella (Light & Motion) and Cygolight. In my (limited) experience the brands seem fairly equivalent at a given price point in terms of brightness and battery life. The really important consideration becomes how far ahead do you need to see? (aka how fast are you riding at night). My personal bias has been to buy the most expensive lights I can afford. The really expensive ones get close to as bright as a car headlight.
I like to have 2 bright lights - one on the helmet and one on the handlebars. The one on the helmet will illuminate where you are looking, which won't always be where your handlebars are pointed - especially if you are cornering at speed, which will involve countersteering. The one on the handlebars I have pointed down a bit to make sure I spot potholes and obstacles - it doesn't need to be as bright as the helmet one. Just be careful to look down when talking to anyone - otherwise you'll ruin their night vision for a while!
I have also learned the hard way to carry a small light AAA powered light in my pocket, just in case one of the main lights didn't take a charge or I'm riding longer than expected (it's happened on a couple of double centuries), or for when I'm riding and there's a chance I'll still be out after dark, but don't plan to be. A bad light is still better than none at all, and will make sure you are visible to drivers.
JB