wp_get_current_user always returns 0 continued

I have been busting my head trying to get the user ID with every piece of code possible but it always comes back “0”. Not sure what I’m doing wrong. I started out using this:

<?php $user_info = get_userdata(1);
  echo 'Username: ' . $user_info->user_login . "n";
  echo 'User level: ' . $user_info->user_level . "n";
  echo 'User ID: ' . $user_info->ID . "n";
?>

Which kicks back a bunch of Function undefined errors which I take care of with “require_once” calling files such as pluggable.php, user.php etc… In the end, no more errors and the user is “0”. Then tried this:

<?php
$current_user = wp_get_current_user();
if ( 0 == $current_user->ID ) {
  echo "Not logged in.";
} else {
  echo "logged in";
}
?>

Which returns another function undefined: Fatal error: Call to undefined function wp_get_current_user() in …. Take care of that with the require_once list of files and I get “Not logged in” everytime. Then I went global with this:

<?php global $current_user;
      get_currentuserinfo();

      echo 'Username: ' . $current_user->user_login . "n";
      echo 'User email: ' . $current_user->user_email . "n";
      echo 'User first name: ' . $current_user->user_firstname . "n";
      echo 'User last name: ' . $current_user->user_lastname . "n";
     echo 'User display name: ' . $current_user->display_name . "n";
     echo 'User ID: ' . $current_user->ID . "n";
?>

And I get this Fatal error: Call to undefined function get_currentuserinfo() in…. Putting the slew of require_once calls and I get this result:

Username: User email: User first name: User last name: User display name: User ID: 0

Not sure what I’m doing wrong. Out of desperation I even tried moving the file into my theme folder thinking that that might work but nothing.

Can anyone help me out??? Thanks in advance!