Is there a phone number that I can call to talk to a live person about concerns I have with my 83 year old father?

We are only live in the sense that we actually exist; we're not available for private, real time conversations. You can, I suppose, contact the administrators of the forum and ask a question, or you could PM one of us.

Your dad is living at home and you are concerned about him.  Is it his care, his health, his finances?  Is someone taking advantage of him?

I agree that calling his doctor, or your local Area Agency on Aging are two good ways to talk to a live person about your concerns.

People need at least a vague idea what kind of help you need: a health condition? elder law? medicare or medicaid? something else?

What about your medical team? It's really hard to make suggestions w/o any further information, i.e., are you looking for more care? Are there specific medical issues? Do you need financial or other help?