G--------------------------------|
D-7-7-0--7-7--7-0----------------| Repeat this a load of times.
A--------------------------------|
E--------------------------------|

G--------------------------------|
D-7-5-3-2---7-5-3-2-0------------|Put this in every so often, you can sort of
A--------------------------------|feel when they are about to come on because he
E--------------------------------|starts to slide his voice down.

P.S You could also tune to drop D and then play it on the e string.  It also sounds 
good.

Have fun and enjoy!