I took on my plot two years ago with the usual horror story of weeds, debris and neglect.
After the clearing, the first year was trying to see what would grow based on experimentation and hints from from other plot holders on what works and doesn't on the site.
What became apparent was that not only was the soil exhausted but so shallow in places the stony sub layer had become mixed in. To add into the mix there was the roots of bind weed, rampant raspberries and other pernicious weeds.
I got myself a rotary sieve (trommel) to use with a generator and started to run the dry soil through the sieve. It worked really well much better than I expected. Stones and large root came out the back into a wheel barrow, bits of broken root fell out with the fine soil underneath but because they are white, easy to pick out alongside any glass slivers. The added bonus is that as the mound of fine sieved soil forms, smaller stones roll down the sides so you end up with a mixture - fine tilth for seeds, soil with smaller stones, gravel. Plus once the weeds have been picked out of the large stone barrow you have another useful item.
The good thing is that it only needs to be done once and if like me, you purchase a sieve it can be sold on to another person.