See link for the suggestion.

http://groups.google.com/group/alt.h...d36071c9ae06be

I sort of wish I'd left the stump a little longer and bought a winch, but
the thought of the chain whizzing past my head or damaging the anchor tree
did not turn me on. So I decided to go the digging out root (ha-ha). This is
looking like a 10+ hour job including the shed hole, only two hours invested
so far. Although I'm nowhere near exposing enough of the stump to get under
the tree. It's been insert shovel, use grub-axe to break roots, remove half
a shovel of dirt. I have to remove about 3 cubic yards for the shed hole and
I've only move about .5 yards so far. The stump is now too short to winch
it out, but some pressure might help me expose the roots to help with the
excavation?

Trees are two spruce trees about 8" in diameter, but I suspect they share a
common root. Site is not accessible by vehicle, dynamite is not an option,
waiting is not an option. The stump is about 16" above ground and must be
excavated to 10" below grade. Possible anchor tree is a Mountain Ash about
12" in diameter.