I drove two ground rods about 6' apart at the service entrance and tied them together with two #6 solid copper conductors running together that then go up into the box. Can't remember if I then pulled a ground conductor over to the main house which is about 40' away, or if I just used the Uffer ground for the house with no conductor to the main breaker panel. Just don't recall, but the inspector liked it.
I haven't gotten around to it yet, but plan to put lightening rods at both ends of the peak. These will bolt to the heavy iron skeleton and carry the current to ground through any or all of the 25 bolted down post pads. The foundation has 25 3' square pilings that go down at least three feet and are all tied together with a perimeter stem wall and footing. An 8" thick radiant slab with #3 bars in both directions on 12" centers ties the entire perimeter together into one big chunk. All of the footing an piling bars are tied directly to the hold down bolts and the heating slab rebar array. That should do it.