I have been playing guitar for well over 10 years now. I never went to class, just play by ear. It was easy for me because i had the interest. But, im not the singalong kinda guy, i play almost everything but jazz, but recently, going back to indie rock.

It took practise and more time on ur musical instrument to master listen and play...

not forgetting also to know all the basic chords

Well, I would say that these aural skills can be improved - of course if you have perfect pitch to begin with it can make things much easier AT FIRST. Perfect pitch by no means will get you anywhere - it can just make your start easier.

Work by building up your relative pitching.

I'd start by learning intervals - so, get someone to play back 2 notes and figure out the interval between them (eg, C-F is a perfect 4th, E-C minor 6th, etc etc). I think this is probably the best way to get started...

After that, you can move on to chords - you should be able to differentiate between major/minor by the intervals between the notes, etc.

Another thing - sing in a choir or do sightsinging! Even though this is not playing by ear, it will train you to sing different intervals between notes. This will help your relative pitching a lot.

Well there're lots of other things.
Yamaha in fact concentrates a lot the ear - aural skills. Although I think they lack in the 'sight' area.

yeah agree but it will help a lot when u found some new songs u like and cant get the tabs.. like me i cant find marcus miller's tabs not in the internet.. not in the music stores.. cant find the books.. even if can find.. would cost at least 100bucks

Hehe... I always have an impression that people who can play electone, can play piano too. Perhaps it's because of Norah Jones?

Anyway, impromtu playing/improvisation is a skill itself that can be practised and perfected.

who needs fkin theory
FEEELLLL THE NOTES!!!! JIMI STYLE!!
lol

doesnt sound good? turn up distortion!!!
LOLOL