how to check if a user account is locked out in linux

Show accounts with password failures
sudo /sbin/pam_tally2

Login           Failures Latest failure     From
jack.oregan         1    06/29/12 15:22:19  /dev/pts/0

Reset all failures
sudo /sbin/pam_tally2 -r

If you run "sudo /sbin/pam_tally2" again the output will be blank