well lets see first off you need better than autozone rotors and you need to make sure that your mechanic no matter how goo they are, are not over torqueing your rims when they put them back on.
i had the same trouble with mine, it seems to be a trademark for the 4th gen's. powerslot rotors stopped almost all the warping on my rotors so you can check them out first. dont bother with anything that says cross drilled they are worthless. just get the slotted ones and then check back with us and tell us how much you like them.....
you should also get some good brake pads like hawks or something else nice. check out thunderracing they have a good deal on brake packages