the firstway to play this song is to play these chords either open or with bar 
chords, chordssound better, in my opinion:

Intro: A(for two measures),D E 
           

           G  C D
If I had a hammer
                  G  C D
I'd hammer in the morning
                  G   C
I'd hammer in the evening
              D
All over this land
              G
I'd hammer out danger
                 C
I'd hammer out a warning
                C     G        C               G
I'd hammer out love between my brothers and my sisters
C            G C D
All over this land


          G  C D
If I had a bell
                   G  C D
I'd ring it in the morning
                   G   C
I'd ring it in the evening
              D
All over this land
             G
I'd ring out danger
               C
I'd ring out a warning
              C     G        C               G
I'd ring out love between my brothers and my sisters
C            G C D
All over this land


           G  C D
If I had a song
                   G  C D
I'd sing it in the morning
                   G   C
I'd sing it in the evening
              D
All over this land
             G
I'd sing out danger
               C
I'd sing out a warning
              C     G        C               G  
I'd sing out love between my brothers and my sisters
C            G C D
All over this land


                G  C D
Well I've got a hammer
               G  C D
And I've got a bell
                     G  C
And I've got a song to sing
              D
All over this land
                   G
It's the hammer of justice
                 C
It's the bell of freedom
                     C     G        C               G
It's the song about love between my brothers and my sisters
C            G C D
All over this land


Good luck with the song
if you still have to ask you please report gmx.net under my e-mail address a.staerker@gmx.net 

Regards alex