This is a tricky question, so help me as far as you can, as google
answers groupies or answerers:

I have been "following" gravity-based power for a while. The promise
is huge -- a 20x20x20foot sandbag under a house would take how much
gas to lift one inch? In practice, the field seems to be ominously
empty. The devil is in the details, but even these appear to be
yielding a little. I'm not an expert, I don't have a device though I
could make one with abyssmal inefficiency, I'm pretty sure.

I figure I've got at least the makings of a Discovery episode if I put
some effort into this, which I think provides a charitable tax
deduction in the event of failure, but don't quote me on that yet. As
a moral being, I know the most open way to launch this business is
what's known as a pink sheet OTC listing. It would not allow widows
and orphans to buy shares because it would not be "blue skied." The
non-blue-skied pink sheet stock is supposed to be sold only by those
willing to take the loss when selling to the poor, like the company
itself, or a hedge fund or big investor.

Anyway, that's the morality involved from someone who likes to think
they make conscience a priority.

Here's my question:

A) it's obvious where I'm trying to go: get the thing made using the
american dream -- is this question askable at Google?

B) If Google isn't where this question can be asked, where is?

C) If Google is where this question can be asked -- answer it.

Is your question:  "What is the best way to get this funded?"

Or is your question "How much gas will it take to lift that sandbag?" 
If this is the question then it brings in more questions with it:
What gas (hydrogen?  helium?  air?...)?
Will it be lifted by a balloon type object above or below it or will
the gas simply be pumped in below it at such a fast rate that it blows
the sandbag off the ground?
Do you want the gas to keep the sand lifted or is it just going to get
it lifted to 1 inch then drop it?

Or do you have some other question that I didn't get from your "question"?

I'm not even sure what this thing will be expected to do.