Steering Pulling To The Left? (possibly A Noob Question)

Clubman 1979:

basically the car constantly pulls to the left, theres not really any more detail i can go into that i know of apart from it constantly pulls to the left... i noticed it slightly when i bought the car but recently i needed to adjust the rear hi-lows, so i did, the left side needed raising (im now thinking it was originally lower than the right) so i went and raised both sides by the same amount, this seemed to make the problem worse, however after adjusting the right rear hi-low back down a little bit it doesnt seem to have made any difference (the left hi-low now sits higher than the right).

For a start I'd get the front suspension checked and aligned, costs about £20 to get the tracking done on a mini at most places.