If I keep entering the incorrect password for an account at Windows 7 start up, do I get a notification when the account is locked? Or does it only come up once I enter the correct password, after too many incorrect attempts?
I haven't tested it outside a domain environment for Windows 7, but typically you get no notification whatsoever that your account is locked out. Once it's locked out and you enter the correct password, you will receive the same message as if you had entered the incorrect password.
This is by design. If they gave you some clue to when you were entering the correct password or when the the account was locked, you could alter your attack pattern to take advatage of the system accordingly. It's the same reason systems say "username or password incorrect" and not just "username unknown" or "password incorrect" (although some poorly designed systems will do this). Limiting the information from faulty logins is how the system protects itself. It's also why most domains will not list the username of the previous user on the login screen. There's no need to give a potential attacker a valid username.