Why would you want to do raised bed gardening ? The main advantage I found is that the earth in the raised beds warms up earlier in the year. So earlier planting leads to an earlier harvest. There are a number of ways to create raised beds. I have used both wood and cinder blocks. The cinder blocks take up a bit more space, but also give you little cubby holes to plant small plants. The other advantage of cinder blocks is that they absorb heat during the day and then release it over night, so keeping your plants in a warmer climate. Raised bed gardens also lend themselves well to square foot gardening.
"Perception is a mirror not a fact"