Japan doesn't have much in the way of Deli or Club sandwiches. They do however have the fast food franchise "SUBWAY" which is wonderful if you can get into the city and actually find one.
As for me, I've resorted to making my own deli sandwiches. This is my personal favorite, a roast beef with black pepper-cheese, with the vegetables (your choice) doused in Italian vinaigrette dressing. I personally like lettuce, tomato, and onion which has soaked for fifteen minutes in the vinaigrette, lightly toasting the bread, add some mayo and sesame mustard, and if you want to pull out the flavor just right singe the roast beef slightly and voila! A deli sandwich like no other!