The best resource to direct anyone is to the GAA website itself.

They have a whole section called “My GAA” that is just full of information and resources.
Click HERE
Spend some time and go through it. 

My GAA
* Getting Involved
* Players
* Coaches
* Match Officials
* Administrators
* E Learning
* Community & Health

My GAA – Players
* Player Welfare
* Transfers / Sanctions
* Anti-Doping
* Managing Injuries
* Fitness & Nutrition
* Player Safety
* GPA