if you go, they will need to pay for everything and give you a
notarized letter stating so and you gave them no compensation in
return. Such a letter is admisable as testimony in a trial, and you
will still be sent a letter and asked to document that you did not
expend any money in cuba. This must specify clearly that they also
paid your plane ticket, entry fees, exist fees, visa fees, hotel stays
(if you stay in a hotel), food and transportation within cuba.

you are right, the original letter of the law was to stop us citizens
from spending money. But, presidential orders from Bush, and many of
them, have clamped down on everything. Example, you used to be able to
go as part of a school program. Now you can't. Pretty much all of
the loop holes have been closed and methods of getting in. It's very,
very, very risky as the President has directed the Coast Guard to
"seize any vessels under any flag capable of going to Cuba" and the
treasury department to "use the full measure of the law to enforce the
trading with the enemies act". There are more treasury agents
assigned to do this then to track down terrorist funding.

Write you congressmen, but until it changes, and Bush leaves, you can't
go.