My father passed away in Dec 2011, I am now receiving his bills as far as
Hospital, ambulance, funeral, etc. I'm wondering, I am not an only child, I am
On disability myself, am I responsible for my fathers bills? Thanks for any help
You can provide.

YOU are not responsible for his debt, but your late father's estate is.
The actual funeral is a different matter.

Not unless you signed for the bill at the hospital.

Does your father have a will, who is going to take care of his estate ( assuming he has one)

The hospital and other bills from when he was alive needs to be processed though his health insurance he had at the time.
Who ever is handling your fathers estate ( money in the bank, cars, houses and the such) would set up an estate account pay the bills according to state law ( in the US) and dispose of property to pay the bills.

As for the funeral, who ever arranged and signed for the funeral will be paying for that.