Who do I contact for an address change regarding a theft charge against me?
You have asked a few questions, so I will take them one at a time.  I suggest you contact the clerk's office for the court in the jurisdiction where the crime took place.  The "case number" that you have might be the police report number, not the court case number, which are different.  The clerk's office will be able to tell you your court date, which you must appear for.    You should also ask the clerk how to go about reporting the address mistake.  Chances are, they will advise you to tell the judge on your court date, who will then order the clerk to note the correct address in the file.  Second, with respect to the penalty, there are usually diversionary programs available to first time offenders for these types of crimes.  In any event, I suggest that you consult with a local criminal defense attorney in the interest of obtaining the best possible resolution of this matter.  Good luck.