People have been using this method for a very long time and its been called many different things. Some of them being sheet composting, no dig garden, no weed garden, etc... It has become increasingly more popular because of a book written by Patricia Lanza, Lasagna Gardening: A New Layering System for Bountiful Gardens: No Digging, No Tilling, No Weeding, No Kidding! Patricia describes the way that her grandmother grew everything she needed to live on and how she has adapted those methods and built on them. Like I said people have been doing this for a long time I think that Patricia is just the first to put it all into words, and she did it well. It's a very easy read. She also has another book on lasagna gardening that is dedicated to herbs, that may interest some of you that want to get your hands dirty but want to start on a smaller scale. If your serious about getting into gardening I think its one of the better books out there.
So back to what a lasagna garden actually is. A lasagna garden is a system of layering materials in a manner that stops weed growth from beneath the garden and provides constant nutrients to the plants by continually breaking down organic matter throughout the season from within. Essentially your planting a garden in a giant compost. Here is a diagram of what went into the layers of my garden:
