Song: Thinking Of You
Artist: Katy Perry
Album: One Of The Boys
Tabber: DJRPlaysGuitar
Tuning: Standard

Well, the first tab I found for this had the right idea, but I think these sound better

Update - Feb 23: Changed the C#m and F#m chord for more open sound (thanks joeschmo88) 
the bridge a little.

Chords used
e|----------------------|
B|----------------------|
G|--9---6---6----8---2--|
D|--9---7---6----9---4--|
A|--7---7---4----9---4--|
E|------5--------7------|
    E   A  C#m   B  F#m

Note: There is another guitar in the song that I haven't figured out yet.
And figure out the strumming pattern for yourselves.

Verse 1

Chord Progression - E, B, C#m, A

e|---------------------------------------------------------------|
B|---------------------------------------------------------------|
G|--9-------------8------------------------6---------------6-----|
D|--9-------------9------------------------6---------------7-----|
A|--7-------------9------------------------4---------------7-----|
E|----------------7----------------------------------------5-----|
Comparasions are easily done, one you've had a taste of perfection. Like an

------------------------------------------------------------------|
------------------------------------------------------------------|
----9-------------8------------------------6----------------6-----|
----9-------------9------------------------6----------------7-----|
----7-------------9------------------------4----------------7-----|
------------------7-----------------------------------------5-----|
  apple hanging from a tree, i pick the ripest one & still got the seed

Pre Chorus

Chord Progression - B, C#m, A, B, C#m, A, F#m

---------------------------------------------------------------------|
---------------------------------------------------------------------|
-8------------6--------------6----8--------6--------------6-----2----|
-9------------6--------------7----9--------6--------------7-----4----|
-9------------4--------------7----9--------4--------------7-----4----|
-7---------------------------5----7-----------------------5----------|

You said move on, where do I go?  I guess second best is all I will know


Chorus

Chord Progression - E, B, C#m, A, B, E, B, C#m, A, F#m

---------------------------------------------------------------------------|
---------------------------------------------------------------------------|
------------9------8----------------6---------------6-------------8------9-|
------------9------9----------------6---------------7-------------9------9-|
------------7------9----------------4---------------7-------------9------7-|
-------------------7--------------------------------5-------------7--------|
Cause when I'm with him, I am thinking of you, thinking of you. What would you do if you
the one

----------------------------------------------------------------------|
----------------------------------------------------------------------|
---------8------------------6------------------------6-------------2--|
---------9------------------6------------------------7-------------4--|
---------9------------------4------------------------7-------------4--|
---------7-------------------------------------------5----------------|
who was spending the night. oh how I wish that I was looking into your eye

Bridge

Chord Progression - C#m, B, A, B, C#m, B, A, B, C#m, B, A, B, A, B, A, B

e|-----------------------------------------------------------|
B|-----------------------------------------------------------|
G|---6---------8---------6------8----------6---8------6----8-|
D|---6---------9---------7------9----------6---9------7----9-|
A|---4---------9---------7------9----------4---9------7----9-|
E|-------------7---------5------7--------------7------5----7-|
  The best and oh I do regret  How could I let myself let you go

e|----------------------------------------------------------|
B|----------------------------------------------------------|
G|---6---8-------------------6--------8-------------------6-|
D|---6---9-------------------7--------9-------------------7-|
A|---4---9-------------------7--------9-------------------7-|
E|-------7-------------------5--------7-------------------5-|
    and now, now the lessons learned. I touched and I was burned

e|-----------------------------|
B|-----------------------------|
G|---8----------6----------8---|
D|---9----------7----------9---|
A|---9----------7----------9---|
E|---7----------5----------7---|
     Oh I think you should know

Song Order-
Verse 1
Pre-Chorus
Chorus
Verse 2
Bridge
Chorus x2


It wouldn't suprise me if there are any mistakes, seeing as it's my first tab.
But I think it sounds right.
Enjoy.