The chords are the same throughtout the song.  And gladly there's only 3 chords; A, G, 
D.  nothing else.

D                                          G
Ive been cheated by you since I dont know when
D                                        G
So I made up my mind, it must come to an end
D
Look at me now, will I ever learn?
D                                    G
I dont know how but I suddenly lose control
G                        A
Theres a fire within my soul
G     D   A
Just one look and I can hear a bell ring
G    D    A
One more look and I forget everything, o-o-o-oh

D
Mamma mia, here I go again
G
My my, how can I resist you?
D
Mamma mia, does it show again?
G
My my, just how much Ive missed you
D
Yes, Ive been brokenhearted
A
Blue since the day we parted
G
Why, why did I ever let you go?
D
Mamma mia, now I really know,
G
My my, I could never let you go.

D                                                G
Ive been angry and sad about the things that you do
D                                                  G
I cant count all the times that Ive told you were through
D
And when you go, when you slam the door
                                            G
I think you know that you wont be away too long
                            A
You know that Im not that strong.
G    D    A
Just one look and I can hear a bell ring
G    D   A
One more look and I forget everything, o-o-o-oh

D
Mamma mia, here I go again
G
My my, how can I resist you?
D
Mamma mia, does it show again?
G
My my, just how much Ive missed you
D
Yes, Ive been brokenhearted
A
Blue since the day we parted
G
Why, why did I ever let you go?
D
Mamma mia, even if I say
G
Bye bye, leave me now or never
D
Mamma mia, its a game we play
G
Bye bye doesnt mean forever
D
Mamma mia, here I go again
G
My my, how can I resist you?
D
Mamma mia, does it show again?
G
My my, just how much Ive missed you
D
Yes, Ive been brokenhearted
A
Blue since the day we parted
G
Why, why did I ever let you go
D
Mamma mia, now I really know
G
My my, I could never let you go