The best way to do a low fat lunch is to make it yourself. Don't go to any chain fast-food places or restaurants since many of their food is fried in lard. Make yourself a turkey sandwich (on wheat) with low-fat mayo, lettuce, and tomatoes. Pack an apple and a cup of yogurt. That's usually my lunch everyday except I usually put some cheese on my sandwich.
Also, see if your local grocery store makes sushi. The Super Targets and Publix have a sushi department. It makes for a very healthy lunch.