These are tabs to the acoustic version of "Assassin" John Mayer performed in 
a seminar at Berklee College of Music. I've added the lyrics from the album version for reference.

http://www.youtube.com/watch?v=bp9w7q04hvs



  Gsus2/B  Gsus2  Bm(add9)  Aadd9  Gadd9    C9      C7b9       G
e---x--------x--------x--------x--------x--------x--------x--------x
b---x--------x--------x--------x--------x--------3--------2--------x
g---7--------x--------7--------6--------4--------3--------3--------4
d---7--------7--------11-------9--------7--------2--------2--------5
a---10-------5--------9--------7------- 5--------3--------3--------5
E---7--------3--------7--------5--------3--------x--------x--------3


VERSE:

               Gsus2/B
I work in the dead of night
       
          Gsus2
When the roads are quiet

      Bm(add9)
No one is around

       A (add9)
To track my moves



            Gsus2/B
Racing the yellow lights

            Gsus2
To find the gate is open

              Bm(add9)
Shes waiting in the room

           Aadd9
i just step on through.



PRE-CHORUS:

         Gsus4/B                    Bm(add9) Aadd9
        O whoa whoa whoa whoa...  O whoa whoa whoa whoa

Gsus4/B         Bm(add9)        Aadd9             Gsus4/B
        You get in, You get done, and then you get gone

                 Bm(add9)         Aadd9                Gsus4/B
        You never leave a trace or show your face you get gone

                      Bm(add9)          Aadd9           Gadd9
        You should have turned around and left before the sun came up again

                    Aadd9
        But the sun came up again



CHORUS:

 Bm(add9)    Gsus2/B       Gsus2          C9/C7b9
I was a killer, was the best they'd ever seen

 Bm(add9)    Gsus2/B       Gsus2          C9/C7b9
I'd steel your heart before you ever heard a thing  

 Bm(add9)    Gsus2/B       Gsus2     C9/C7b9
I'm an assassin and I had a job to do

 Bm(add9)    Gsus2/B       Gsus2             C9      G     C9/C7b9
Little did I know that girl was an assassin too...