Dan Mcl,
As far as cooling your wort. Get a wort chiller. The faster you cool and pitch your yeast the more stable you final product will be. Slow cooling increases the chance of "hot side aeration" which causes beer to oxidize. Wort chillers are easy to make.
Sorry for the hijack.
For copper tubing go to Home Depot and get it in the A/C section.
If you make a basic still you can distill the water out of many liquids including sea water.
Bill