Order JO7110.65U: ATC

http://www.faa.gov/air_traffic/publications/atpubs/atc/
http://www.faa.gov/documentLibrary/media/Order/ATC.pdf

AIM

http://www.faa.gov/air_traffic/publications/ATPubs/AIM/aim.pdf
http://www.faa.gov/air_traffic/publications/ATpubs/AIM/index.htm

PCG
http://www.faa.gov/air_traffic/publications/atpubs/PCG/pcg.pdf
http://www.faa.gov/air_traffic/publications/atpubs/PCG/index.htm

AIP

http://www.faa.gov/air_traffic/publications/atpubs/AIP/aip.pdf

Skew-T

http://www.nws.noaa.gov/om/aviation/front/04feb-front.pdf

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_120-71B.pdf