The picking pattern for the intro and first verse goes like this:

e |--------------------------------------------|
B |--------------------------------------------|
G |--------------x-------------------x---------|
D |-------------------x-------------------x----|
A |---------x-------------------x--------------|
E |----x-------------------x-------------------|

Intro/verse
Use your index finger to get the notes on the G string, and bar the rest with your middle.

e |----x---------x---------x---------x---------|
B |----x---------x---------x---------x---------|
G |----8---------7---------5---------5---------|
D |----9---------7---------5---------5---------|
A |----9---------7---------5---------5---------|
E |----9---------7---------5---------5---------|

Chorus (I've got a long black river...)
Stay on the last chord (G Maj) until the chorus ends.

e |----x---------x---------x---------x-----x---------x---------|
B |----x---------x---------x---------x-----x---------x---------|
G |----1---------3---------5---------8-----7---------5---------|
D |----2---------4---------5---------9-----7---------5---------|
A |----2---------4---------5---------9-----7---------5---------|
E |----2---------4---------5---------9-----7---------5---------|

The outro is pretty much the same as the intro for the next song 
on the album, "You Got Cool", but slowed down. That tab can be found here:

http://tabs.ultimate-guitar.com/m/mansions/you_got_cool_tab.htm

Thats basically it! Any questions, email me at edzirko@ymail.com