These tabs were carefully instructed by David (DKstorms101). But all props go out to Black Sabbath.

Intro
G--------------------------------------------------------------------------------------------------|
D--------------------------------------------------------------------------------------------------|
A-----------0-0------------------5-5-----------------0-0------------------5-5-5-5-------------|
E----2-2-----------0-0---2-2----------0-0---2-2-----------0-0---2-2--------------0-0-0-0--|

Pre-Chorus
G-----------------------------------------------------|   Repeat this 10x then play the chorus 
D----------------7-6-4-------------------7-6-4-----|    immediately after.
A------------------------7------------------------7--|
E--5-5-5-5-5--------------5-5-5-5-5--------------|   

Chorus
G------------------------------------------------------------------------------------------------------|
D------------------------------------------------------------------------------------------------------|
A-----------------5-----------------------------------5-----------------------------------------------|
E---2-0-2---2-0---0-2-4-5-4-2-0---2-0-2---2-0----0-4-5-4-2-0---5-5-5-4-2-0---0-0-0-4---|

Chorus (continued…)
G-------------------------------------------------------------------------------------------------------|
D-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-(play this in about 8 seconds)---------------------------|
A-------------------------------------------------------------------------------------------------------|
E-------------------------------------------4-5-5-5-4-2-0---0-0-0-4---2-0-2---2-4-5-4-2-0-0-4-|

Chorus (continued……)
G-----------------------------------|
D-----------------------------------|
A---------------4------------------|
E-2-0-2---2-0---0----------------|

After Chorus repeat the Pre-Chorus and the Chorus except once u finish the chorus the next time, you repeat the Intro and then lead into the Bass/Guitar solo.

Bass/Guitar Solo
G-------------------------------------------------------------|  Repeat this 4x but on the last time
D---4(8x)-2-2----------------------------------------------|  instead of the ending (2-0-2-0-2-0)
A----------------5(8x)-4-4-2(5x)--------------------------| you play open E for 4 seconds.
E------------------------------------5-4-2-0-2-0-2-0-2-0-|

After the solo repeat the Intro then Pre-Chorus then Chorus and then finally end the song with the intro slowly fading away as you finish.