The timing belt should have been changed at 60K miles on your year car, so what you were told about changing it is correct. As far as all the other things that you were told, ie: valve cover gaskets, air cleaner, spark plugs, oil change, etc., most likely is correct also. I think the prices you were quoted are pretty much in line. All of these maintenance items are pretty normal for a car of your year and mileage. How much $$ did the mechanic tell you he'd charge for the timing belt change?