I'm digging post holes in my yard for a fence and have come upon hard
clay soil with tons of tree roots below. I cant get my shovel more
that 2 inches deep. I have to finish my fence because i have half done
all this work to get 1/2 up already. The one side was very moist and
muddy but the trouble section is hard/clay like cememnt.

What are the tools and options I have to inexpensively get these holes
dug? Is there any reasonably priced machine that I should use? I'd
rather do manually if anyone has any tricks....