There are 2 guitars in the song, Dave Murray and Janick Gers. You can hear both guitar parts played together in the Normal Speed Audio (under Tools in the Menu). However in this ActionTab we remove Janick's guitar and look solely at Dave Murray's guitar part. Both are similar, but typical of Maiden, the guitarists play different harmonies together and the solos are different.
As far as Maiden songs go, this song isn't too difficult to pick up - except for the solos, which are difficult and we advise skipping them unless you are ready (or insane).
When learning this song, don't worry about the speed - that will come with practice.
The Song can be divided into the following parts (they are often repeated at various points in the song so just switch between them when necessary):
Part 1 - Intro Riff, this is used again later in the song. Use Distortion.
Part 2 - Switch to a clean guitar sound for this part. Dave does the backing chord picking (just pick through powerchords - very easy stuff). Janick plays a little melody over this part.
Part 3 - The fast part. This is the 'nod your head' riff and is not too hard to do...just remember that every note is double-picked (down / upstroke), and you'll get up to speed with the melody in no time. Apply distortion, naturally.
Part 4 - Just strike and hold simple powerchords as Bruce jumps in singing. Doesn't get much easier than this.
Part 5 - Pretty typical metal chugging riff for the Chorus ('fear of the dark...fear of the dark' sung here). Use some palm muting downstrokes and open chord strikes.
Part 6 - Just do the riffs from Part 3 again, however at the end of that is a new riff for the Interlude (This is how Maiden play it now that Adrian is back, and it's a great little bit of guitar).
Part 7 - This is the simple backing guitar part played whilst Janick does his solo.
Part 8 - Solo time. Leave it unless you're advanced enough to give it a crack, it's a hard one.
Part 9 - This is a nice little harmony. Here we see Dave's part. Much easier than the solo!
That is all the main song parts. From that point on just apply them as required. The only other new bit is towards the end of the song, where some muting is used (during the last chorus).
Notice that each of the above parts is really just a straightforward riff (or two) that repeated a few times before moving on to the next song part. So even though the song is quite long, there isn't masses of stuff to learn!