Hello. This is a specific question. I know a person who models and has had many photos taken by professional photographers. I'm thinking of using one of his photos on the cover of my book. Would he own the rights or the photographer? What's a fair price to offer him or the photographer for the use of the photo? Maybe someone can point me in the direction where this kind of question can be answered. Thanks.
I believe the photographer would own the rights. Contact him and ask if you can use it. You may be able to get use for free as it will be good exposure for the photographer but you'll have to discuss that with them.
In the US, I think in that scenario you just described, the photographer will likely still own the rights to that image unless there's some document or proof that says otherwise. Contact him/her and request permission. I wouldn't even mention anything about compensation -- let them bring it up (that'll tell you how "pro" they really are, btw).
On top of that, you'll likely also need a model release. Just because the photographer owns the rights to the image doesn't mean s/he got the proper model releases for all uses. Again, another test of how pro the photographer really is. Since the model is your friend, I gather, this shouldn't be a problem, but may as well get all your ducks in a row.