Need help with P0336 code

[Andy H]

I have a 2000 camaro 3.8 v6 m5 with 88k miles. My ses light came on the other day. Autozone read the code and said it was P0336. The only thing I have noticed my car doing is twice, the engine has missed. When the engine missed, it was only one jerk. Also, my gas mileage has went down. I have done a search and read a lot about the code it gave. I have read all kinds of stories on how to replace the crankshaft position sensor. None of the stories are the same. Can anyone help me out here? Do you think the sensor is bad? If so, do I have to pull the harmonic balancer off and buy a new bolt to reinstall it with? Also, will I have to take the car to the dealer to do a relearn procedure? Thanks!