Channel and Frequency Guides

HF Radiotelephone Channels
Complete duplex and simplex channel plan available for download.
http://www.navcen.uscg.gov/marcomms/high_frequency/default.htm

US Coast Guard NAVTEX
Information about worldwide NAVTEX coverage.
http://www.navcen.uscg.gov/marcomms/gmdss/navtex.htm

VHF Marine Radio Channels and Frequencies
U.S. VHF Marine Radio Channels and Frequencies Commandant (G-SCT-2) U.S. Coast Guard
http://www.navcen.uscg.gov/marcomms/vhf.htm