Slair
Believe the question has been answered a few times. Do understand t could be an interpretation thing however. There is not any single source in the UK for the ATPL exams.
To obtain our fATPL or CPL/IR we went to a school which provided us with a distance learning course OR a full time school based course.
That course can only be provided from a JAA approved school registered for the purpose of providing these courses and the materials within that course are inspected by the CAA to ensure that the content/depth etc are suitable for the purpose.
If you wish material to help you just type in JAA ATPL exams in google if you want a course then go online and search for a school which is registered for the purpose.
I suggest
www.bristol.gs
I have no vested interest and cannot say that they are better or worse as I only did the course once.
The course however was excellent and comes on CD and folders so that you can choose your preferred method. I chose this self study method and took about 16 weeks to complete the 14 exams but that was hard going about 14 hours a day 7 days a week. The support was excellent. I must say one thing that is I have never met anyone civil or military, rotary or fixed who did not think the Bristol course was excellent and I think it would take a brave man to say that about a many other schools.
Good luck.