the oil filler neck and cap can be bought for about 25 dollars. pry the back of the neck up under the tab with a large flathead screwdriver and twist counterclockwise and it will come off. (they leak all the time).
there is no gasket for the baffles on the valve cover. it is just rtv glue. these are notorious for leaking like crap! remove the small torx screws and the two large torx bolts before the actual valve cover bolts. then pry off the baffle. take a flathead again and carefully pry against the fuel rail. it's okay you'll be good. makes it easier to remove then if the whole valve cover is off. to not overtighten the small bolts when reinstalling. they snap very easier and strip the threads!
by the way if your car has some miles on it or if the breather hoses look a little dry, order the 2 on driver's side as they crack during removal sometimes. the one on the passenger side comes off easy!
Jason