Articles contain a lot of practical advice and tips from other folks going off the grid.
The Alternative Energy Store Has very low pricing and fast on-line ordering for all types of solar and wind energy products and systems. An essential resource in helping to determing how much solar energy your area of the US receives for all times of the year. North Carolina State University's Solar Center NCSU's Solar Center contains a plethera of relevant information on solar power. Again, another great resource from the US government. Sandia Labs has done lots of research on many practical aspects revolving around solar energy.