Ok - I have a few answers!
As I suspected, using a laser on a tourmaline isn't common. There's hardly any information available on it. Irradiation, heating and to an extent fissure fillling yes but not laser drilling. However, if this stone really has evidence of laser drilling it could be because:-
(a) The stone didn't have any rutile needles, a laser could be used to add some in. This is incredibly deceptive.
(b) The laser was used to aid the process of fracture filling. You've got to ask that if this stone has been filled then (1) is it stable and (2) What has it been filled with? Tourmalines can be oiled/filled with an epoxy or resin.
Whatever the case, IF this stone has been laser drilled, it's virtually worthless. Interestingly, one of the experts said that he believes this stone started off nearly black and has been heated to achieve the colour it is now. Obviously that's just his guess and may not be right as it's very difficult to tell from a photograph. Heating of Tourmalines has been a pretty common practice and irradiation is now prevalent also.
So should you buy it? Well, it's up to you. I wouldn't touch it with anybody''s bargepole.
If I get any more information, I'll post it up.