You can find the VPN credentials and other lab details by clicking the "OUTPUT" in the reservation details within the sandbox portal - https://devnetsandbox.cisco.com/RM/Reservation/List (click your reservation).

As for the emails not coming through... the email system is working (I received one myself a few minutes ago), so checking that your updated email is correct in the system and checking spam filters are the first steps I'd suggest.
Thanks Hank!