These are some of the ship trackers that are available on the
web. Some trackers are a subscription service but these are all
free, though they may have adverts or limitations. They all operate
in a similar way, using the
AIS signal broadcast by the ship. The actual controls and facilities
offered, and also the coverage, varies betwee the sites, so try them out and
pick one that you can get on with.
If none of these work well for you look for more with a search
engine using "ship", "vessel", "tracker", "finder" and similar words.
"AIS" might help too.