This is mostly based on the tablature at http://tabs.ultimate-guitar.com/d/
don_mclean/empty_chairs_tab.htm - I'm extrapolating chords from the notes played 
there, and simplifying a bit when it seems appropriate. You could probably get 
away with simplifying more, though in the original the guitar is of course very 
much picking out a full melody.

G (320003@1)                              Asus2 (x02200@1)        AmI (x02210@1)feel the trembling tingle of a sleepless night
C (x32010@1)              D7 (xx0212@1)             GCreep (320003@1)through my fingers and the moon is bright
G (320003@1)      Gmaj7 (xx5432@1)name="chord_320000@1">G6                       Asus2 (x02200@1)      AmBeams (x02210@1)of blue come flickering through my window pane
C (x32010@1)                   D7 (xx0212@1)           GLike (320003@1)gypsy moths that dance around a candle flame

G (320003@1)    Asus2 (x02200@1)name="chord_x02210@1">Am
And I wonder if you know
     Cadd9 (x32030@1) D7 (xx0212@1) GThat (320003@1)I never understood
     Em (022000@1)         Am7That (x02010@1)although you said you'd go
C (x32010@1)             D7 (xx0212@1)              G (320003@1)name="chord_xx5432@1">Gmaj7 G6 (320000@1)name="chord_x02010@1">Am7 Asus4Until (x02230@1)you did I never thought you would

G (320003@1)                                 Asus2 (x02200@1)        AmMoonlight (x02210@1)used to bathe the contours of your face
C (x32010@1)                      D7 (xx0212@1)            G (320003@1)      
While chestnut hair fell all around the pillow case
G (320003@1)      Gmaj7 (xx5432@1)           G6 (320000@1)        Am (x02210@1)        Asus2 (x02200@1)name="chord_x02210@1">Am
And the fragrance of your flowers rest beneath my head
  C (x32010@1)         D7 (xx0212@1)                GA (320003@1)sympathy bouquet left with the love that's dead

G (320003@1)                Asus2 (x02200@1)AmAnd (x02210@1)I wonder if you know
Cadd9 (x32030@1)D7 (xx0212@1)        GThat (320003@1)I never understood
       Em (022000@1)                  Am7That (x02010@1)although you said you'd go
C (x32010@1)             D7 (xx0212@1)              G (320003@1)  Gmaj7 (xx5432@1)name="chord_320000@1">G6
Until you did I never thought you would

Asus4 (x02230@1)           Em (022000@1)                G (320003@1) Am7Never (x02010@1)thought the words you said were true
D6 (xx04xx@1)  G (320003@1)         D6 (xx04xx@1)      C (x32010@1)      Am7 (x02010@1)name="chord_x02210@1">Am CNever (x32010@1)thought you said just what you meant
Dsus2 (xx0230@1)D (xx0232@1)            G (320003@1)       Gmaj7 (xx5432@1)name="chord_320000@1">G6 Am7Never (x02010@1)knew how much I needed you
       D (xx0232@1)          C (x32010@1)      D6 (xx04xx@1)    Am (x02210@1) D6Never (xx04xx@1)thought you'd leave, until you went 
G (320003@1)                                 Asus2 (x02200@1)  AmMorning (x02210@1)comes and morning goes with no regret
C (x32010@1)                    D7 (xx0212@1)       GAnd (320003@1)evening brings the memories I can't forget
G (320003@1)    Gmaj7 (xx5432@1)   G6 (320000@1)      Am (x02210@1)      Asus2Empty (x02200@1)rooms that echo as I climb the stairs
C (x32010@1)                    D7 (xx0212@1)              GAnd (320003@1)empty clothes that drape and fall on empty chairs

G (320003@1)                Asus2 (x02200@1)AmAnd (x02210@1)I wonder if you know
Cadd9 (x32030@1)D7 (xx0212@1)        GThat (320003@1)I never understood
       Em (022000@1)                 Am7That (x02010@1)although you said you'd go
C (x32010@1)             D7 (xx0212@1)  G (320003@1)  Gmaj7 (xx5432@1)name="chord_320000@1">G6
Until you did I never thought you would

Am7 Asus4 D7 E7 C D C D C D G