Well, buying the blinds early in any tourney or sit and go definately, is kinda fruitless; the amount of risk u take for the amount of chips u get isnt worth it. Not to mention that developing a tight image, will allow you to buy pots later in the tourney, with better reward for ur risk.
Theres a good video on the full tilt academy website for the middle rounds and later rounds of larger turbo tournaments. Other than that, all i know is if you're in a Turbo thats an SG, once you hit the money, play for first. Forget getting second and third, your goal should always be first at that point.