I have 2 distillers from Sears (about $100).  
They also sell the cleaning powder, but white vinegar works great, too.
One of the distillers I found new, unopened at a yard sale - yippie!!!
Another distiller I own (but haven't used) is distills water and extracts 
essential plant oils.
http://www.keystonehomebrew.com/index.cfm?pgid=spirits
The 1 gallon is $325 and I paid around $425 for the 7-gallon size.
You can also distill alcohol with them, but that's illegal in the US and most 
states.
http://www.stillspirits.com is the maker of this distiller; with pages of 
instructions you can read.
Hope this helps! Mary