Hey TK,
Hopefully this would help:
For MET, remember the exam is 100 Q's and it is much more detailed than the SAMRA as the 100 Q are all directed at strictly meteorology.
The books I used are:
1. Air Command Weather Manual
2. Aware
3. Aviation Weather from Jeppesen
4. Meteorology book from the UK (Sorry, can't remember the name)
Just to give you and idea, I was quite suprised that I actually got a few Q's on Tropical Meteorlogy and also the Complex Low Q's as well. So I am sure they can ask you just about anything.
For Operations:
1. From the Ground Up
2. The Turbine Pilot's Manual
3. AIP
4. Aerocourse book which I borrowed from a friend
5. CFS
6. Fly The Wing
This may not be a comprehensive list but it has helped me get through the exams.
I hope this helps. Even though the exams are Free, you still want to try to pass them at the first go. My impression is that the MET is definitely the harder of the two.
Let me know if you have other questions...drop a PM.