The only info I have is that he is somewhere in Illinois and has been in trouble before and is around 20. He has my same first and middle name which is Christopher Michael. Any ideas?

Do you know his lastname? Is it the same as yours? You might try going to the library and bringing up public records of arrests or court proceedings or convictions in Illinois.

Also depending on what kind of trouble he got into, you might want to look through newspaper clippings if you know the approximate time that he may have been arrested. You may also want to try "People Search" or Reunion.com Just Goggle them, and you may get more ideas.

Good luck!