I worked with a driver that used a headlamp light (like what's used in mines). Pretty effective, particularly in an area I'd never been in where the people liked to put gardens in the strangest places!
to say the least. -Rocky
I don't use a headlamp at work, but if I did, I would use one like this.
http://www.rei.com/product/721995. I have one similar to this that I use for caving and setting campsites up in the dark. Petzl also makes a lot of cheaper versions. LED lighting is the way to go, bright lighting and long battery life. I used to carry a small Maglight in my pocket.
As far as finding addresses in the dark, this comes with experience and area knowledge. Like posted by others, you will go to some addresses just about everyday. If I have to find a street in the dark running EAMs in an unfamilar area, I will look in a mapbook and count streets and which way to turn. For example: Turn left off the highway onto connector road. Turn right after counting five streets, then the destination street will be second street on the left. Start reading house numbers off mailboxes and figure out which way the number breaks go. The "corner houses" can be tricky, they may face one street but the address will be the side street. Sometimes there is a weird house which is numbered wrong, like an odd number on the even side of the road.
(after using it for 20 plus years at UPS I considered it my "gold watch" when I retired")
