For those of us who are "code junkies", just plain curious, or simply insomniacs, I'd like to pass on this link for absolutely free online access to the entire collection of the NFPA codes, including the NEC! You can't print or download (that privilege will set you back $1,395) but you can look up all those pesky grounding questions to your heart's content:
http://www.nfpa.org/freeaccess
I know this is old news and has been previously alluded to twice on CR4, but only for specific documents, so here's the complete set.
"Almost" Good Answers: