Try ABC supply, Bradco, or Spec. Just about any roofing supply company
will sell a device called by different names, but around here we call
it the "laddervator". It is a device that attaches to your extension
ladder and simply pulls a trolley up and down the ladder carrying its
I think they are about $1200.
Around here, we have the shingles roof loaded by the delivery company
for a small charge. We put the felt, nails, tin caps, tar, jacks, and
water bucket on the roof while the delivery truck is here. They have
an extension device which goes to the edge of the roof. One man loads
the extension, and the other catches the material.