Here is another trick I have used.
I went back into our woods to where there are a lot of leafy trees, where it is in constant shade and even on hot days feels cool and damp. I took a bunch of top soil from this area for a few of our raised flower bed, and any plants that are in pots.
I am guessing any place that is undisturbed and in leafy trees should do. if it has moss over it, it seems even better
You can just tell this stuff is good, its very black and fluffy.
I avoid needles, they are (in my area) high in acids. This might work great for the rose bushes and a few types of garden veggies, but never to good for what I generally plant.
I am not sure if you have any friends around with forests, or if it even would resemble what I have here, but for those who may, its been a rather good trick for me.