How to query two more input in laravel 3's validation?

You can create a custom validation method as a catch all. The major problem here is that the validation extension will only ever pass the single attribute to the method rather than the values of all three. This will require you to hack up the validation. This method will be very bespoke to your particular application due to the hard coded nature of the table, column names and input. It also does not give you any way of telling which field the issue is with and would require some additional rule. Another suggestion would be to actually extend the validator class as a library to provide you with a much finer tuned validation engine for this circumstance.

Validator::register('usercheck', function($attribute, $value, $parameters)
{
    $count = DB::table('user')
      ->where('userName', '=', Input::get('userName'))
      ->where('email', '=', Input::get('email'))
      ->where('status', '=', Input::get('status'))
      ->count();

    return $count > 0;
});

To use it just add it as a rule... bear in mind this feels a bit hacky and there ARE better ways of doing this, most notably the method I suggested in the opening paragraph.

$rules = array(
    'userName' => 'usercheck'
);