Who should I consult to assist in my POA duties now that Mom has passed away?

A power of attorney ceases to be effective once the principal, here your mother, dies. Therefore you no longer have any authority under her POA to act for your mother, or your mother's estate.

I do not know what you now need to sort out. It's likely you, or someone, needs to handle her estate"”all the property she owned when she died. If she had a minimal amount of property (the precise dollar figures varies by state), no formal legal proceeding will be required. If she owned more than a minimal amount of property, there must be a valid legal transfer of that property to whoever is to inherit it. The first step here is to find out if your mother left a will (or other valid property-transfer device, such as a living trust.) If there is a will, court probate proceeding must be filed. Normally, the executor appointed in the will hires a lawyer to handle the probate. If there is no will, an "Intestate" probate proceeding must be filed, which again requires hiring a lawyer.

There is no public agency or free service I know of that can give you help with handling your mother's estate. The best you can do is to educate yourself on what is legally required in your state. One good source of information is Nolo, a self-help law publisher in Berkeley California. [I have written several books for them.] I specifically recommend that you read "The Executor's Guide," by Mary Randolph, a thorough explanation of what's involved in handling someone's estate.