Whenever I turn left in my '08 Malibu 2LT I hear a knocking noise, after about a 1/2 turn of the wheel. I also can feel this knock, or pop, when my foot is on the brake or gas pedal. This does not occur when I turn right. In no way does it effect my turning or driving, it just worries me that there could be a big problem.
Is this something I need to be worried about? My car is still under factory warranty so this should be covered.

Seems to be an issue most of these cars have. Yes it is covered, when I took mine in they were able to make the necessary repair (some sort of adjustment) in a matter of hours. Take it in and get it fixed.

Sounds like the steering rack to me, discussed on here MANY times. Bring it in.

i think my car might have this problem how much would does it normally cosst to have someone fix this

Try spraying a lubricant like rust check on the universal joint in the steering shaft. It stopped a similar knock on my 04 that the dealer couldn't correct
Hank