Today is some quickie links for calculating solar power needs.
http://www.freesunpower.com/system_sizing.php system sizing, this ASSUMES a big house, adjust accordingly.
http://www.davidrumsey.com/luna/servlet/detail/RUMSEY~8~1~206663~3003208:Average-Number-of-Hours-of-Sunshine# for sunshine maps to calculate the hours of sunlight per month and average season.
http://www.wunderground.com/calculators/solar.html Finally the weather undreground has a very nice solar database that can give you details in a graph for your location.
http://www.energymatters.com.au/climate-data/ This one has nice graphs showing solar and wind outputs.
http://www.wholesalesolar.com/StartHere/OFFGRID/OFFGRIDCalculator.html A nice solar system calculator to get you estimates.