These simple bag garden plans are from the book Starter Vegetable Gardens. It's a 3 year plan. This idea is pretty genius, I think, as it's minimal effort, really cheap, and creates 3 foot wide rows which I think are ideal.
What I like is that you buy a cheap $2 bag of top soil and grow some shallow rooted veggies for one year and end up with the weeds all smothered beneath without even digging. Stack several side by side and you end up withr a 3 foot wide garden row. Then cover the edges with hay to hide the bags.
Year 2 bag garden plan:
Year 3 bag garden plan:
Pretty bag garden example (although it doesn't use the top soil bag):
With top soil bag: