"And who are you", the proud lord said, "that I must bow so low?
E|--------------------------------------------|
B|-----1-----0-----1--3--0-----3--1--0-----0--|
G|-----2-----2-----2-----2-----2---------2----|
D|--2-----2-----2------------2----------------|
A|-----0-----0-----0-----0-----0-0------------|
E|-----------------------------------------3--|


  Only a cat of a different coat, that's all the truth i know."
E|-----0-----------0--1-------1--0------------|
B|-----1-----3-----1----3-----3----3--1--0----|
G|--0--0--0--0--0--0----0--0--2---------------|
D|----------------------------0---------------|
A|-----3-----3-----3----3---------------------|
E|---------------------------------------0----|

  "In a coat of gold, or a coat of red, a lion still has claws
E|--------------------------------------------|
B|-----1-----0-----1--3--0-----3--1--0-----0--|
G|-----2-----2-----2-----2-----2-----2---2----|
D|--2-----2-----2------------2----------------|
A|-----0-----0-----0-----0-----0-----0--------|
E|-----------------------------------------3--|

  and mine are long and sharp, my lord, as long and sharp as yours."
E|-----0-----------0--1-------1--0------------|
B|-----1-----3-----1----3-----3----3--1-------|
G|--0--0--0--0--0--0----0--0--2----------2----|
D|----------------------------0---------------|
A|-----3-----3-----3----3----------------0----|
E|--------------------------------------------|

  And so he spoke, and so he spoke, that Lord of Castamere,
E|------------------------------------------------|
B|-----0--1-----1--1--0--------0--1-----1--1--0---|
G|-----------2-----------0-----------2-----------0|
D|--2-----------------------2---------------------|
A|-----0-----------0-----------0-----------0------|
E|-----------------------0-----------------------3|

  but now the rains weep o'er his hall, with no one there to hear.
E|--------------0--0--------------------------------|
B|-----0--1-----3-----3-----3--1-----0--1-----------|
G|-----------2--2--------2--------2--------2--------|
D|--2-----------0-----------------------------------|
A|-----0-----------------------0-----------0--------|
E|-----------------------------------0--------------|

  Yes, now the rains weep o'er his hall, and not a soul to hear.
E|--------------0--0-----------------0--------------|
B|-----0--1-----3-----3-----3--1--------3--0--1-----|
G|-----------2--2--------2--------2--------------2--|
D|--2-----------0-----------------------------------|
A|-----0-----------------------0-----------------0--|
E|------------------------------------0-------------|

I took this one http://tabs.ultimate-guitar.com/t/the_national/the_rains_of_castamere_tab.htm and edited it a 
bit to make it sound better and to make it more similar to the version that plays in Game of Thrones