If you like the Sopranos (I certainly do) and haven't seen them yet, try Sons of Anarchy and Underbelly. Also back the rec for Boardwalk, and if you can somehow get it (actually I can sort it if you want) the current Irish gangland drama Love/Hate is just immense!
Po, are you watching that, as an Irishman? What do you think, if you are, and why not, if you're not?