I have a 2001 Nissan Frontier and the lights are no where near bright enough. What can I do to get them brighter?

If you are using factory light bulbs I would try going with a brighter replacement bulb. I was having the same issue with two of my cars. I went to auto parts store and found the brightest bulb that would plug directly into my factory bulb sockets. Then adjusted the light beam height for the newer brighter bulbs. Now I can see real well. And did not have to spend a bundle of cash to do it.

Are the clear plastic lens over the head lights foggy/cloudy? You can pick up a cleaning kit at an auto parts store that restores the plastic lens to it's original clear state. Or you can go to a professional auto detailer and they can restore them for you but for a higher cost.