Weird, your code seems to work for me:

import java.util.Arrays;

public class Test
{
    public static void main(String[] args)
    {
        // args is the list of guests
        Arrays.sort(args);
        for(int i = 0; i < args.length; i++)
            System.out.println(args[i]);
    }
}

I ran that code using "java Test Bobby Joe Angel" and here is the output:

$ java Test Bobby Joe Angel
Angel
Bobby
Joe

Assuming you are running some variation of the bubble sort algorithm, and that you have not sanitised you input array for null strings, the problem is likely that organizedNames[i] is null.

If this is the case you need to decide if you want to remove null items, or list them at the end of the array. If the latter is true, prior to doing a comparison, check if name1 == null || name2 == null if so, set num to -1, this will put all the null items in an array in one place.

To answer your secondary question, try this:

boolean done = false;
while(done == false){
  done = true;
  for(int i=0;i<organizedNames.length-1;i++)
  {
    int num = 0;
    if(organizedNames[i] != null && organizedNames[i + 1] != null)
    {
        String name1=organizedNames[i]; String name2=organizedNames[i+1];
        num=name1.compareTo(name2);
    }
    else if(organizedNames[i] == null && organizedNames[i + 1] == null){
      num = 0;
    }
    else if(organizedNames[i] == null){
      num = 1;
    }
    else {
      num = -1;
    }
    if(num>0)
    {
        String temp=organizedNames[i];
        organizedNames[i]=organizedNames[i+1];
        organizedNames[i+1]=temp;
        done=false;
    }
  }
}