Pixguy, that ceiling looks very good. Clean, neat job!
I did similar to pixguy but more low tech.
I used bent coat hangers for hooks and suspended some spare pipe at either end of the plastic and one for the middle.
I then just laid several sheets of the corrugated roof plastic on these with a little overlap. Lot's of "stuff" filters thru the porch so I take it down every once and a while to rinse off.