Looking for parts info

Hi guys,

I am new to Skylines. I just bought a 1991 GTS-4 and I really like it. It’s obviously not as fast as my friends GTR but is still a fun car.

Anyways, I am ready to to the first tune up since I bought it and my local parts distributors can't find any part #'s for anything (ie: plugs, filter, etc). I had a quick look on the form but did not see anything like this. Is there an online parts and tech manual or anything like that that a guy can get his hands on? Also is there a factory recommended service schedule for other components (ie: tranny, driveline, etc.). That a guy can get? 

Any help would be great.

Thanks a ton,

Travis