I am so sorry for your loss.  This must be a very difficult time dealing with all of this.  What you need to do is to be appointed as the personal representative of the estate of your Dad.  Once you are sure that you have all the creditors then you can indeed negotiate with them.  There are certain requirements for publishing to alert creditors of the death of a person to allow them to make a claim. Here are links that might help.  Good luck.http://www.cobar.org/index.cfm/ID/20909http://www.denbar.org/index.cfm/ID/20881