I have the same car, and I replaced the spark plugs myself. The spark plugs should cost $1.80 each (retail street price) for NGK V-Power. You need four of them. Labor should be about 0.75 hour or less. So at a shop that charges $75 an hour for labor, the cost should be $57 for labor, around $8 for spark plugs, plus fees for shop supplies (including anti-seize lubricant and di-electric tune-up grease) and taxes.
An air filter costs $10 to $16 (retail price at NAPA) and installation fees should be minimal. A fuel filter costs $18 to $30. I don't know about labor costs.
A spark plug wire set from NAPA costs $44 to $61 (retail street price). Installation fees should be minimal if you're getting them changed when you're having the spark plugs replaced.
I wouldn't use the cheapest place. But I'm guessing that the cheapest places are the national chains, like Pep Boys, Midas, Meineke, etc. Or maybe a dirty local garage in the city.
One note of caution: it is easy to snap off a bolt when removing the air intake tubes to get to the spark plugs on the left (when facing the car from the hood). The technician has to be very careful and use a lubricant spray. The bolts are not tough.
