Suggestions on travel between locations to/from a tour

Hi, I'll be arriving at Narita Airport terminal 2 and need to get to Tokyo to start a tour. I'll then need to go from Osaka back to Narita terminal 2 by train, after the tour. My questions are...

1. What train lines would you suggest for these 3 trips (Narita - Tokyo, Osaka - Tokyo, Tokyo - Narita)?
2. Would all of these train lines be covered by the JR Pass or would I need to purchase one in addition to another pass?
3. Where am I able to book these trains or look at their timetables?

Thanks!