Ok well no one else has posted so I'll bite!
At the barn I board at our footing is mainly the natural soil with some sand mixed in, it is quite clayey and so packs. It gets harrowed daily with a quad and harrows and about once every 4-6 weeks they bring in the big tractor with the tills and work it up and harrow it with the big tractor again. Tilling it makes it too deep, but harrowing it with the tractor packs the footing down just enough that it ends up a really good depth. They also harrow in wood shavings (not sawdust) every once in a while as well.
They say money doesn't buy happiness -- well happiness doesn't buy horses!