Station Siting:
http://home.comcast.net/~dshelms/CWOP_Guide.pdf
Snow Measuring:
http://www.nws.noaa.gov/om/coop/snowguid.htm
Data Collecting/General:
http://www.wxqa.com/archive/obsman.pdf
http://www.nws.noaa.gov/om/coop/training.htm
http://www.ofcm.gov/fmh-1/fmh1.htm
WMO GUIDE TO METEOROLOGICAL INSTRUMENTS AND METHODS OF OBSERVATION
http://www.wmo.int/pages/prog/www/IMOP/publications/CIMO-Guide/CIMO_Guide-7th_Edition-2008.html