It is down very close to the oil drain plug, mounted horizontally. Very easy to see. Like most new cars, it is not the old oil filter that you have on the 2007 Corolla, but a canister type. You use a 65mm 14 flute cap wrench to remove it. Don't unscrew it all the way at first - let the oil drain out before pulling it all the way off. Pull out the old filter element and old o-ring, clean up the canister, then put in new filter element and lube the o-ring, put on o-ring, lube the o-ring again, and screw it back together. The instructions are on the box of the Toyota filter. I highly recommend using a Toyota filter, from dealer or order on-line from a dealer. Order a case from the right place on line and it is much cheaper.
Youtube has some good videos if you want to see it there first.
One piece of advice - remove the canister filter first, then the drain plug.
It is not hard at all IF you have the proper cap wrench.