I understand that one did not need to have one's btc on an exchange in order to get the bch but it was easier.
How does one go about taking ownership of any of these other coins based on btc ownership at the time of that new coins creation and which are they?
Go to wikipedia, see the date and on what block fork happend. if at that time you store bitcoin in your wallet you can claim the forked coin at their official website by export your privatekey from your wallet and import it there, make sure thats the real website not a phising web.