I think the best way for a lot of things is to probably just cover it with leaves in the fall and then in the spring throw a few inches of compost on top of them and plant in that... digging and tilling it up just stirs up the weed seeds etc. and you end up with a bunch of weeds. Plus all that digging is for the birds.
Just planted some lettuce like this today... I filled in the sunken walkways of my tilled up garden spot with some branches and sticks because they were turning into stagnant ponds when it rained a lot., then piled up about a foot of leaves over it last fall and just threw some dirt on top of some of it today and planted in it.