I agree with Martin some what if your trying to copy,
some one else's solo's or songs.
I think one of the hardest things to find when your,
useing your hear to copy solos or songs is the octave,
of the note the other person is playing out of.
Plus the fingering thier useing.
Any more if i can hear the note i can play the same,
note.but that come's from playing more than 3 years.
If your getting 50 or 60 percent of the notes right,
thats not bad for only playing 3 years.
Make sure you try to match your note against the note,
the person is playing untill you think they sound the same.
The bass notes are easer to find when useing your hear,
but when the other person is playing on the B or high E
Strings then its real easy to play the wrong octave of,
his notes.
Plus experiment with other fingerings the guy could be,
playing almost backwards to the way you finger your notes.

Mark