you probably need to clean your MAF sensor. It is located directly on top of your throttle body. Then, after removing the screws and pulling out the MAF, you can spray the little wires down with some QD Electronic cleaner. If that does not work, you will probably need to replace it with a new or used one. They are very expensive new.
You also need a new oxygen sensor. It is located on the rear exhaust manifold, and looks like this, (differen connector!)
it is a good idea to use the special tool to get the old sensor off, you can rent it at most parts stores. it helps to have the exhaust WARM... not HOT or COLD
if you have more questions after this, just post them up!