Hello,
I just changed the oil on my step son's '03 sunfire and when I took off the intake hose, I noticed there was oil in the intake silencer, the part that the hose connects to before it goes to the throttle body. Is this common?

For emissions reasons the normal engine blowby (which has gas and oil vapors) get sucked back into the engine and burned up rather then vented to the atmosphere, the finger thick hose going form the intake to the valve cover is where it gets pulled out of the engine and back into the intake tract, along with it will come very small amounts of oil that will slowly acumulate to something.... which is what your seeing. It's completely normal, you will see it on pretty much every single car on the road now days.