https://bitcointalksearch.org/topic/same-public-key-246544
Somehow I didn't find, mayby because I was looking for wallet and not public key.
Anyways - can I find anywhere how EXACLY are public keys generated? How random are they?
Sure. You can look in the source code.
I believe that the keys are generated with a call to EC_KEY_generate_key() from the OpenSSL library after a call to RandAddSeedPerfmon()