IMy house has a staircase with 14 stairs and 15 risers.Until this past winter, only one of the stairs was creaking.(walnut wood) Since then the whole staircase is creaking, and very badly. The house is close to 100 years old but each slat is firmly in. I just occurred to me - there was a hurricane in this area about 2 years ago that actually caused my roof to separate from my house a few inches. I need an opinion as to whom to ask about the stairs.

Look at ads locally for carpenters and builders and home renovators. The trouble is that you need someone who is very knowledgeable about the entire building process, and that can vary a lot from person to person. Most people go by word of mouth. Who worked on your roof, and did they do a good job (or did you leave it the way it is)?
You can leave your stairs the way they are, and of course the walnut is very valuable, if it's actual walnut wood. Whoever works on it has to examine the whole structure to see where the stringers and other supports under the stairs have moved or detached from (what I assume is) the wall on one side of the stairs. It could be expensive. I'd be more concerned about the house as a whole, and I would ask someone with a full builder's license to look at everything. You can ask a few people for quotes.

Thanks so much for you quick reply. The trouble is that one contractor can satisfy one person and be only cause for trouble to another person. I've had a flat roof above a den that has cost me more than my house (purchased in 1961). 'so many leaks that I have no trust in the last roofer or any others.

I hear you. I think I would live with the creaky stairs. I doubt they are going to fall down unless the house falls down.
Many a flat roof owner has resorted to building a sloping roof right over it after countless grief and promises of new techniques. I don't know of a roof that doesn't have inherent problems. Even metals ones have the problem of moisture entrapment.