I've often used Sail&Rail tickets to travel between Ireland and the UK. Seat61 tells me that Sail&Rail is also available from the UK to the Isle of Man. However, I cannot find out whether I can use Sail&Rail between Ireland and the Isle of Man. (Tickets from the Republic of Ireland or Northern Ireland would do.)
The Seat61 site has an embedded booking form from Rail Easy, but that just says "No journey found".
Well one reason why this is not in the rail booking system is probably due to the very few scheduled ferries between Ireland and Isle of Man.
According to Steam Packet Company, there are 2 round-trip possible in the next 6 months, around Christmas.
Bahn.de/OBB do not give any schedule after December 8, 2012 so it would not be included. RailEasy just gives a basic "schedule not found", and loco2 does not know Douglas anyway.
So the best option is to just book a ferry and a train separately (is Rail&Sail a cheaper combined ticket?). Steam Packet Company has a page with Sail&Rail offers that does not refer to trips to Ireland.
