Who made forks?

According to the site The history of eating utensils, the forks were introduced by the Greeks, atleast to the western history of eating utensils. See,
http://research.calacademy.org/research/anthropology/utensil/forks.htm

These following books could give you more information:
Petroski, Henry. The Evolution of Useful Things. New York: Alfred A. Knopf, 1992.
Giblin, James Cross. From Hand to Mouth: Or, How We Invented Knives, Forks, Spoons, and Chopsticks & the Table Manners To Go With Them. New York: Harper Collins Publishers, 1987.