The cutting edge of lo-tec. Windmills built from scrapped airplanes, home made wood fired steam engines, battery maintenance advice etc.
Otherpower's forum. Very hands on and useful
Probably the most extensive list of updated solar links
Hand on DIY solar info
Useful tools to see what sort of stuff you need.
One of the best collections of links
Air collectors like these can one the gist of how to build them. (most of the functional parts of this design can be scavenged)