Intro; this isn’t quite right but sounds ok to me
Hold a Dmaj9 chord with index finger and keep pulling off
The D note with your ring finger, let it sound a bit and hit the A note, 
do this repeatedly, listen to original song for the rythym.

riff
E|---------|
B|---------|
G|---------| end up in G, next time played in C
D|---0-0---|
A|--0---2-0|
E|---------|

D     G           D          G                    D      F#m                             
Home is where I'm going No matter how long it takes  And I've been

                      Bm         G                    Asus     A
living high 'n' free, love It's time for me to try another way

 D             G           D      G                   D   
I think I'll send her a postcard  So she can meet my plane
      

F#m                          Bm        G                        Asus A      
well I don't know what I'll say to her I've caused her so much pain 
      
G                          D    Riff
Houston I'm a coming to see you

G                               D  Riff   C
Hoston has it really been that long     I know I've been away

    G                                               play intro
But I'm just calling to tell you I'm leaving today


D         G          D          G                             D
sitting here in San Francisco Lord I'm trying to get more pay

    F#m                              Bm
you know it's good to hear your voice again

G                                Asus A     D    G                     D
you say the words I like to hear you say,   now I'm trying to read your letter

   G                D     F#m                        Bm
It's been almost a year  it did me good to get away from you

G         C              Asus A G                         D  riff
now I'm wishing you were here  Houston I'm a coming to see you

G                               D riff   C
Houston has it really been that long  I know I've been away

G                                              D  intro
but I'm just calling to tell you I'm leaving today

G                           D riff G                              D riff
Houston I'm a coming to see you    Houston has it really been that long

G                       D riff
Houston Houston Houston ( yeah I'm coming to see you )

G                               D riff
Houston has it really been that long

G                        D riff
Houston Houston Houston ( yeah I'm coming to see you ) fade