Ok folks, this song is basically played holding a " G chord shape". You'll get what i mean once you give it a go. Basically your 3rd finger, or ring finger, is held in position when playing a G chord. It stays there throughout the song, while most of the fretting is done with your 1st and 2nd fingers. Ok, here we go, dont forget to get the strumming pattern down - pat, as it is extremely hard to tab out a strumming pattern.
There are 2 riffs in this song, so once you've learnt them, you've got it!

intro and verses.

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

Ok, it might look a little difficult, but its not. The strumming is mainly focused on the bottom 3 strings. The fretted B string doesnt really get played, its there for ease of flowing into the chorus. Leaving your finger on the 3rd fret, also helps with the placement of your 1st and 2nd fingers, which do all the work on the note selecting.( To make it sound easier, your 1st finger stays at the 2nd fret, and your 2nd finger stays at the 3rd fret. All they are doing is moving from string to string.) 
Also, dont try to sound each note by itself, it wont work. It has to be strummed at, so no pussy - footing around, just get in there and hit it!

chorus.

      Asus                    Cadd9                  G                             D5
e-----0----------------------0---------------------0------------------------0-------------------------------
B----3----------------------3---------------------3------------------------3-------------------------------
G----2-----8counts-----0----8counts----0-------8counts-----2-----8counts------------- D----2----------------------2---------------------0------------------------0-------------------------------
A----0----------------------3---------------------2------------------------0-------------------------------
E----------------------------0---------------------3---------------------------------------------------------

Well thats it, im sure you can count how many verses etc, so just listen to the song to refine it. This is   how i seen john play it, and it is definately in standard tuning, cause he dropped the low E string to D to play his next song which was valley. So i would say that this tab is close to being perfect.
 
Any corrections are welcome, we are all after the perfect tabs! Peace and enjoy