Where is oil filter on Saturn aura?

The 2008-2009, L4-2.4L 4 cylinder Aura oil filter is a replaceable element, not a standard spin-on type. It's on the front of the engine, driver's side, slightly under the intake manifold, next to the transmission. It's accessed from topside. The oil filter cover looks like a short dome with a hex nut on top. You'll need a 1 1/4" (32mm) low-profile socket to remove the cover [i.e., NAPA = SER-3932; Advance Auto = Lisle 14700]. You'll likely find this socket in the Oil Filter Wrench section of your local auto parts supplier.

Your replacement filter should come with a new o-ring. Remove the oil filter housing cover, then remove the old element and replace. Make sure to use the new o-ring. Make sure that the new filter element is oriented correctly before installation.