I have a whirlpool dryer and it want start... I turned my timer on and press the start button and want do anything.. but you can hear a noise at the timer button and when youn go to press the start button the noise stops... I am wondering if its the timer button or the start button?

The only way to really know for sure is to test the timer and the start button.

However, before tearing the dryer apart, just check the door switch to make sure its working properly, it should be right on the underside of the door.

Basically what will initiate the dryer will be the motor, it is the holy grail of functions. Nothing works unless the motor turns. Not saying the motor is faulty, but the best test would be to press on the start button with time set on the timer and test for voltage (120 volts to neutural) on the motor. Make sure you test to neutural and NOT to ground, this is because by testing to neutural, you are testing both hot and N sides of the line. If 120 volts is present at the motor, yet the motor isn't turning, you could have a faulty capacitor, or motor. If the capacitor is removable, you can replace it for around $5. Note: the motor has a centrifucal switch in it, this provides the latch circuit for the dryer and is also a switch to bring one leg down to the element. So the wiring harness on the motor will have a lot of wires coming out of it, its important to locate the correct wires.

If you do not have 120 volts at the motor, then go to the timer and using the wiring diagram, locate where 120 volts should be coming out and test to neutural there. If no voltage is coming out there when you have the start button pushed, your timer could be faulty, that is if your start button is built into your timer.

If you have an older dryer with a sepearte start button, you will want to test that button for operation. The test is easy. With one lead on neutural, press the button and test the terminals on the start button, both sides should read 120 volts. If one side does and one side doesn't, your start button is bad.

We've been having a lot of problems like yours latley. Its been a while since Ive torn my dryer down and Im working on some old dusty memories here. I am prompted to tear my dryer down today, take some pics for reference and post them here for easy explinatio on how to troubleshoot these components.
Whew- that's a lot of work though, and of course I'll have to check with the Mrs's.