If you are not receiving your password details to the email you registered/signed up with, then please check your mail program's spam and junk folders. You may also have to check with your ISP/mail-host to make sure that they are not screening messages before they hit your inbox.
Check your inbox settings that they are not set to automatically delete messages and that there is no re-forwarding.
Also, there is a common "hosted" email issue. If it's not really a hosted email but rather an email address at one's domain and then it forwards that email to a gmail account so that it "looks" like a hosted, but it is really a forward. In many cases with that type of account, the settings are not configured correctly at the server level and gmail tends to not put emails to those accounts in the ALL MAIL folder, but not in any other folder.
You can also utilize Google narrowing down the search to your email host.