All over the web are a lot of web sites that handles the subject sound
velocity, but i haven't found one yet that is complete enough for me.
I have been searching for a ray trace program, but didn't found one. I did
found a program which can calculate the sound velocity profile, you can
download it for free at: http://nauticalcharts.noaa.gov/csdl/htp/svp.htm
At the site of the NOAA you can find a lot of oceanic and some sound
velocity information (http://www.noaa.gov/).
If you find a good web site or ray trace program, please let me know!!