Hi LadyKat.
As you know, I applied for my fiancee visa whilst living in Tennessee too. I posted all my original documents by Fed-Ex, including both my passport and his passport with no problem.
(We did have trouble getting his passport sent to me by post from the UK, but that's another story! It got 'lost' at Miami Int. Airport for nearly two weeks!!!)
It is a bit scary sending all that stuff off, but it must be done! I made copies of everything I sent off so I at least had proof of them.
But don't worry about sending things to them. Fed-Ex takes good care of things and they will then Fed-Ex your stuff...all of it....back to you.
The only way around giving your passport up is going to NY and doing the visa in person.
Good luck!