I have a basic understanding how the a/c systems work...
I understand how the compressor works or condenser, etc.

What I am looking for is a set of practical instructions
on how to discharge, replace failed components and recharge
system properly. Adding correct levels of oils, etc.

Do you know any good book dedicated to this subject ?
Any website with practical information on A/C repair ?
Where to get replacement parts for a/c systems ?