Hey guys. I bought the game a year and a half ago. Is my rule book up to date? If not, is there a document that I can fully update my rules with? I hear about new rules and want to be as up to date as possible

Here you go:

https://community.fantasyflightgames.com/topic/180455-index-of-useful-links/

Scroll down to FAQ & Other Helpful Documents . Also, the original rules are listed above this section.

Mark the fact that old errated rules may be already in your rule book or on your game material. Depends on how old your stuff is.