Please find budget passenger/cargo ship from Southampton to Grenada in
the Caribbean Next March 2003.  Wish to stay in Grenada fo 2 weeks and
return to Southampton also by ship.  Could embark from alternative
Northern European port (Le Havre, Cherbourg, Amsterdam, Rotterdam,
Liverpool) but would prefer UK port

Hi,

I have been doing some research on this; I don't feel I have found
enough to post a comprehensive answer, but I have found some info
which may help.

The Geest Line is a cargo carrier which sails from Portsmouth to
Grenada; I emailed them to see about a passage, but presently they do
not have to facilities to take passengers - just bananas!
They did advise ringing 'Cargo Ship Cruises' on 01473 736265, who can
help organise cheap sea travel across (I have not pursued this
further, but I would suggest that you give them a call).

I hope that this helps, if I find out anything further I will post it
here.
Regards,
Ali