when I turn on the heater/A.C, it makes a really loud vibrating noise, any ideas

That sounds like something possibly could have got in your blower cage causing it to be out of balance. One possible cheaper and easier fix would be to remove the blower motor, clean debris if there is any in it. Otherwise the blower motor is possibly failing. Bring it in for a free check if you didn't get your problem handled yet. Give us a call at Precision Auto & Tire Pros 262-567-0410