Where is the oil filter located on a 03 chevy cavalier?

The Ecotec engine has a cartridge type filter rather than a spin-on type. It's pretty easy to change. It is on top of the engine block, just under and behind the air intake tube where it goes into the throttle body. Take off the black plastic housing and replace the filter inside. I remove the intake tube for easier access, but you may not need to depending on what kind of wrench you use.