This song has been bouncing around in my head all day--all I can remember is

"clickety-clack, clickety-clack,
the wheels all sing to the railroad track,
that if you go you can't come back,
if you go you can't come back,
if you go-o-o-o, you can't come back."

I did a bracketed search on the digitrad with both "clickety-clack, clickety-clack" and "if you go, you can't come back" with no results. Anyone help me out on this? (I think this song came up in the threads a couple of weeks back--but it just hit me today). --seed