I am injured on the job. I know I have to fill out an accident report form (known as a C-2 in NY State), but from whom do I get it and with whom do I file it ? Do I need more than one copy to file with other people/agencies ?

Your Stage Manager will give you the correct form to fill out. In some instances this will be an insurance company form from which they will fill out the actual C-2. You should make a copy of this form and any other form you fill out and keep a copy for your records.