Mitsubishi Galant

I have a 2004 Mitsubishi Galant that one day last week started to***** slightly while giving it gas on the highway. I went to a nearby advance auto and was advised that one of the spark plugs was miss firing. I was referred to a mechanic for a tune up. The gentleman started the tune-up them called me to say that the coils had oil in them, okay so I advised lets replace the coils, another few hours I recieved another call, telling me the one of the cam-shafts needed replacement. Okay, we go over why he figured that the cam-shaft needed to be replaced, finally the last call of the day was to advise me of the timing belt was in need of being replaced also. And that my car wouldnt start. I'm confused and uncertain if this guy knows what he is doing. And also if he had anything to do all these things that he is learning as he goes thru repairing something else. I dont want to get ripped off. Could you please advise me if these things have anything to do with one another? Should my car not start when it was working fine when I gave it to the mechanic, or could he have done something to cause these problems? Pleaes help me, I am not sure where to go with this as of now?