This is a favorite, I'm glad I can contribute it for the benefit of  others because
it's been a simple but satisfying song to play. There are a couple recordings of this
song and Jeff Mangum sings different lyrics for some of the lines but the chords are
the same.

G-A-C

It's the same three chords repeated throughout, he holds the C chord in a couple places.

    G        A         C           G 
For I am an engine and I'm rolling on
                 A           C             G
the world is all bending and breaking from me
(or:through endless revision to say what I mean)
               A             C               G                     
for sweetness alone who flew out through the window
    A           C                   G
and landed back home in a garden of green
    A               C                   G
               A           C         G
you're riding alone in the back of a steamer
                A            C           G
and steaming yourself in the warm shower spray 
                A          C              G
and water rolls on off the round captains belly
                 A           C             G
who's talking to tigers from his cafeteria tray
               A               C               G
                      A           C             G
and your sweet babies cry for the cool taste of milking
             A            C        G
that milky delight that invited us all
                 A             C           G
and if there's a taste in this life more inviting
                  A           C                           G
than wake up your windows and watch as those sweet babies crawl 
A        C   G              A  C                           G
        awaaay yeah mmm mmm mmm dee dee dee dee dee dee dee dee 
               A                       C                  G
               A                       C                  G