Arthur works at an insomnia hotline [FOUND!]
What I remember is that Arthur works at a hotline for insomniacs, where he just talks to people who can't sleep either until they do, or until he can refer them to a professional. By day, Arthur is an aspiring writer. Eames calls him one night, and it becomes a regular thing. I think Eames (eventually?) reveals he is calling Arthur as a distraction because he's trying to quit drugs and/or alcohol, and Arthur tries to get him to talk to a therapist, but he refuses/already has one and needs someone at nigh? Regardless, I remember that Ariadne takes Arthur to a concert, where Arthur confirms by means of a song Eames wrote part of over the phone with Arthur that Eames is actually a big rock star, and Arthur calls Eames directly after the concert (they traded real numbers at some point), and calls him out on that, and then they get together somehow.
Many thanks for the help. ^^
Many thanks for the help. ^^