Check Craigslist for mushroom compost delivery and also rabbit droppings for anyone who may be happy to give it to you.

Till or dig in copious amounts of pine bark mulch or the partially composted pine bark sold as a soil improver. These are the cheapest you can buy (by volume) here on the Texas coast and they last longer than shredded leaves that seem to disappear during the growing season, but nothing wrong with adding shredded leaves if you have them handy. Your photos make it look like this is the kind of ground that takes several years of improving before it becomes easy to grow on.

After adding lots of leaves and using the city compost, it finally took shape. I also used rye grass a a kind of cover crop, it's been working out so far. I've been somewhat sucessful growing on it.

Here's a most recent photo

I've been getting lots of lettuce off of it.

I'll be planting my tomatoes soon, have a lil bit of prep to do.

Well, I just learned something new last week and I Google a lot about it.

I am in FL and still amending but you can still do it . Check into Cover crops also known as green manure. :)