If you haven't set anything up and use the Account Generator as is, it's one of the Emails we use for generating accounts that was banned by steam. Either try again, or if that doesn't work, use your own domain.
I need the email
If you have the original Login and Password, you can recover the email here.
This will wait for incoming emails (e.g. Account Verification) but also show the email address.
I have lost the password to my account!
Tough luck. Since passwords are not saved in cleartext and there is pretty much no way to prove an account is actually yours, we will most likely not be able to assist you. Keep the accounts' credentials more safe in the future.
No. The Steam Account Generator generates a new Steam Account. That's it. There is no way to add games like GTA V, Forza Horizon or any other game you have to buy to a Steam Account. You will have to either crack the game, or actually buy it like every other decent human being.