First off I've broken the song into segments so as to get some organized 
format for this very un-organized song. I've only tabbed up until the end of 
the 2nd verse, then the brass starts and it's pretty pointless tabbing all 
that. What I've tabbed out is Jonnys martenot for the keyboard and guitar.  
I'm using the same piano instructions as normal.  I will put the note and 
then the number 1,2 or 3 in conjuction so as to tell you where on the 
keyboard to hit the note.
i.e A2 means hit the A note in section 2.
    section 1                  section 2                section3
  C#DEbEFF#GAbABbC           C#DEbEFF#GAbABbC       C#DEbEFF#GAbABbC
                 *middle C
For the guitar note I will put it in brackets next to the keyboard note. I 
will put the string and fret number.
So  A2 (G14)  means the piano is the A key in section 2 and the note for the 
guitar would be played on the G string on the 14th fret.
Here is the main bass riff played over and over throughout the song.

D--------------------------------------------------------------------
A--9----------------9-----------------8--------------7---------------
E-----10---10--10------10--10--10-------10--10--10------10--10--10-10
I've organized the song by numbering it, each number represents every time 
the main riff is played. Any note under that number shows where and when 
Jonny plays the martenot.
1     bass riff starts up

2

3     drums kick in
   D2 (A5)
4

5    drums stop for a half measure and then kick back in
A3 (G14)
6
  Bb3 (G15)
7
A3 (G14)   G3 (G12)
8
F#3 (G11)
9
D3 (G7)
10
Bb2 (G3)   G2 (G-open)
11
F#2 (D4)   A2 (G2)
12
  F2 (D3)      A2   (G2)     E2 (D2)
13
D2 (D-open)    A3 (G14)
14
Bb3 (G15)    G3 (G12)
15
A3 (G14)  F#3 (G11)
16
  Bb3 (G15)     G3 (G12)
17
  A3 (G14)   F#3 (G11)
18
  F3  (G10)
19
  E3 (G9)
20    Verse 1
everyone      everyone
21
around    here    everyone is
22
so  near    it's holding  on
23
      it's holding  on
24
A3 (G14)    F#3 (G11)
25
Bb3 (G15)     G3 (G12)
26
A3 (G14)    F#3 (G11)
27
Bb3 (G15)   G3 (G12)
28   Verse 2
and everyone      everyone is
29
so  near     everyone
30
stop  the fear    it's holding  on
31
      it's holding on
32   Brass enters , Jonny's martenot plays the same thing that was      
played after Verse 1

_________________________________________________________________________

Radiohead - Kid A
'The National Anthem' 
bassline
Tabbed by Aaron Heisler
(gravitygrave_resident@yahoo.com)
Joey Gallagher's tab is pretty good but says you have
to tune the bass drop D - this is unnecessary...you
can actually play it just about anywhere on the bass
without a major change in tuning...anyway this
concentrates specifically on bass....
This song has a terrific jazzy feel to it. Colin's
bassline is quite simple and rather repetitive, so
here it is! (I've tabbed it for five string and four
string basses; if you have a four string, play it on
the D string, but if you have a five string, you can
go an octave lower and use the E and B.) This song is
very similar to another I've heard by someone else but
I just can't put my finger on it :) (Maybe the Two
Lone Swordsmen mix of Spiritualized's 'Come
Together'?) 
Anyway if you would like to make a comment or
correction, or just to chat, send me a mail! :)
Rhythm is fairly strict 4/4 time (phew!).
Ok:
Five string:
E 2-----2---2-1-----1---1-
B -3-3-3-3-3-3--3-3-3-3-3-3
the national anthem - bass
Four string: 
D 4-0-0-0-4-0-0-4-0-3-0-0-0-3-0-0-3-0
etc...