I want to do my own tune-ups on my LS. Gonna change the air filter, spark plugs, maybe the wires, and PCV valve. Oil changes are done on a regular basis.

For the air filter I'm gonna use K&N Stock filter #33-2285.
I don't know what PCV valve to use and where it is located.

The spark plugs look like they will be tough because 3 of them seem to be behind the header, if that is what the big thing on top is called. Never actually saw one before. Anyway, what spark plugs are recommended as well as the spark plug wires?

Are there any complete car care manuals out for the 9G yet, like Haynes or Chilton?

I think you might be referring to the intake manifold. If so, you have to remove it to replace the plugs. I would recommend either Nippon Denso or NGK, but see what the factory plugs are by reading the manual or checking on your car.