Sorry buddy I can't help you but it's good to hear from you. I think far more people than we realize actually take voyages on these commercial vessels that are often equipped with many amenities, not to mention it is usually far far less expensive than a Cruise ship.
Just Google "Freighter travel" and you'll get some answers. From a friend of mine who has done this, you have to be flexible, in good health, easily pleased without a lot of amenities and have a love of the sea.
My friend is a solo female traveler and has done this many times. She felt very comfortable in foreign ports as the crew "adopted" her in sometimes not too friendly ports, and she had made many friends. I have lost contact with her so cannot connect you to her. But, start with Google - and I think Maersk has some freighters that take pax.