Where can I find the transition altitude in different countries or regions?
Hoping to cover as many places as possible. Links to the applicable regulations would be nice.
See also:
What is the difference between "flight level" and "altitude"?
Where can I find regulations in different countries for flight level rules based on direction of flight?
EDIT: Instead of request a list, now the question asks for how to find in general. A few examples should still be given though.