As with most Tossers songs, this requires a capo on the 5th since it's intended for mandolin.
The intro is an Am chord broken up in various ways.  I'll not bother tabbing it exactly 
it appears on the album , just listen to it and play along or create your own variations. 
I usually play it something like this:

e | -----0---------0---------0---------0----- | 
B | ----------------------------------------- | 
G | ---2---2---------2---------2-----2---2--- | 
D | -2-------2---2---------2-----2-2-------2- | 
A | -----------0---------0------------------- | 
E | -------------------3--------------------- | 

Maintain some pattern up to the chorus, and then you can just strum it all from there.  
times the guitar cuts out entirely.  At others you can wail on it.  Just listen to the 
and it will be apparent.

VERSE:
     Am              G
Last night I lay all in my dreams,
       Am                 G
when a rap at the door it startled me.
      Am                    G
And I heard those footsteps on the stairs,
      C         G           Am
And I bade her; please come in.

CHORUS:
     Am              C
Come in, come in, my roving friend.
     Am          G Am
Come in and rest a while.
                        C
For you've been gone so very long,
     Am          G   Am
it's nice to see you smile.
                     C
Come in, come in, my wandering friend.
  Am         G    Am
Accept my welcome home.
                      C                           G       Am
I hope you can stay a long, long while before you have to go.

VERSE:
And she walked across the room to me,
and then she sat right down with me,
and told me that she had to leave.
She could not stay for long.

VERSE:
A child he held into his arms,
a child that I knew well through time,
and told me that he had to leave.
He had to take him home.

CHORUS

VERSE:
She crossed the floor and moved away,
and my heart said, "Stop her. Maker her stay."
But I just showered myself in tears,
for I just let her go.

VERSE:
When I awoke I cried and cried,
and went to sit by his graveside,
and visit the child he left behind.
Because he had to go.

(For the instrumental bit here, repeat the Verse twice)

    Am
You must come back to me again.
  Am
Accept the welcome I extend.
  Am
I will not let you go this time,
   C    G     Am
if only in my dreams
   C    G     Am
if only in my dreams
   C    G     Am
if only in my dreams.
     C     G     Am
Come to me in my dreams.

VERSE:
And yeah, though you walk ever on,
may your heart be not weary but strong.
And yeah, though you walk ever on,
through the valley of the shadow of death.