You might want to try lasagna gardening? Here's one quick link, but there may be better ones out there: http://organicgardening.about.com/od/st ... garden.htm
It can be hard to get enough organic debris to begin with - we've been making one big new bed each year, usually about 1' deep. But you can get a good start with a bottom layer of wood chips, generally delivered free from any local tree service in your area. And if you get extra wood chips, they break down really well in 2-3 years for a continuing supply of organic matter.
Our 2nd layer is usually 1/2 rotted leaves from the autumn before, and the top layer is 2-3 inches of finished compost. The first year works especially well for anything in the squash family or setting out tomatoes or other substantial veggies, and the next year it is broken down enough for root crops and everything else.
Also - you will need to fertilize with a complete fertilizer - I mix my own veganic one, but for small gardens it is easier to buy premixed ones, if they're available in your area.