PrestonPilot best of luck with your course at CTC.
When I was the SGI for them in New Zealand they were using the Bristol notes/CBT and believe that is still the case. I personally would not waste money buying another set of ATPL notes as the Bristol ones are fine.
You didn't say whether you are on an "integrated" or "modular" course and is the ground school going to be classroom based (as it was NZ) or more self-study.
Though in general getting ahead of the game is a good idea it can lead to wasted effort. I remember one student wrote 7 pages of notes taking several hours on Polar Charts which after I explained it came down to 7 lines! Stick to overall concepts not detail PRIOR to the course.
Student weak area tend to be in General Navigation and in particular the use of the whiz wheel (CRP-5 et al). Whiz wheel skill is VITAL to GN. If you can nail this before the start this would be time and money well spent.